…patch

**What does this PR do?**

This PR adds a new test scenario, the `ruby_dir_interruption_patch`.

**Motivation:**

This scenario tests DataDog/dd-trace-rb#3720
in a very unique way: by loading the profiler, and then running the
upstream Ruby test suite for the `Dir` class with our monkey patches
applied.

(For context, our "monkey patches" are a couple of Ruby modules which
wrap the behavior of the standard library `Dir` class, and thus we
need to be quite careful to make sure not to break any existing
functionality.)

**Additional Notes:**

This test does not actually generate or assert on any profiles, it only
checks that the profiler is running and the monkey patches were
correctly applied prior to running the Ruby test suite.

The `mspec_config.rb` file is also quite important, since it ensures
that both the profiler as well as the monkey patches were correctly
applied (e.g. to avoid the test passing trivially because e.g. the
profiler actually didn't start).

Because at time of writing
DataDog/dd-trace-rb#3720 is not yet merged,
this test is expected to fail with:

```
$ TEST_RUN_SECS=5 TEST_SCENARIOS="ruby_dir_interruption_patch" go test -v -run TestScenarios
=== RUN   TestScenarios
    correctness_test.go:210: Considering only scenarios in ruby_dir_interruption_patch
    correctness_test.go:225: Extract base image from: scenarios/ruby_dir_interruption_patch/Dockerfile
=== RUN   TestScenarios/scenarios/ruby_dir_interruption_patch
    correctness_test.go:244: Folder: scenarios/ruby_dir_interruption_patch
    correctness_test.go:245: Json file: scenarios/ruby_dir_interruption_patch/expected_profile.json
    correctness_test.go:246: Docker file: scenarios/ruby_dir_interruption_patch/Dockerfile
    correctness_test.go:248: Built test app with: test-app
    correctness_test.go:137: Running docker command with output /home/ivo.anjo/datadog/prof-correctness/data/ruby_dir_interruption_patch-1618380497
    correctness_test.go:138: '[/bin/sh -c bundle exec ddprofrb exec ruby mspec-master/bin/mspec-run --config mspec_config.rb spec-master/core/dir/]'
    correctness_test.go:151: Error running the test docker run -v /home/ivo.anjo/datadog/prof-correctness/data/ruby_dir_interruption_patch-1618380497:/app/data:rw -u 1000:1000 --security-opt seccomp=unconfined -e EXECUTION_TIME_SEC=5 -e DD_SERVICE=prof-correctness-scenarios/ruby_dir_interruption_patch test-app:latest - /app/mspec_config.rb:3:in `<top (required)>': uninitialized constant Datadog::Profiling::Ext::DirInstanceMonkeyPatches (NameError)

        if Dir.ancestors.first == Datadog::Profiling::Ext::DirInstanceMonkeyPatches &&
                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^
        	from /app/mspec-master/lib/mspec/utils/script.rb:91:in `load'
        	from /app/mspec-master/lib/mspec/utils/script.rb:91:in `block (2 levels) in try_load'
        	from /app/mspec-master/lib/mspec/utils/script.rb:86:in `each'
        	from /app/mspec-master/lib/mspec/utils/script.rb:86:in `block in try_load'
        	from /app/mspec-master/lib/mspec/utils/script.rb:85:in `each'
        	from /app/mspec-master/lib/mspec/utils/script.rb:85:in `try_load'
        	from /app/mspec-master/lib/mspec/utils/script.rb:102:in `load'
        	from /app/mspec-master/lib/mspec/commands/mspec-run.rb:34:in `block in options'
        	from /app/mspec-master/lib/mspec/utils/options.rb:111:in `process'
        	from /app/mspec-master/lib/mspec/utils/options.rb:143:in `parse'
        	from /app/mspec-master/lib/mspec/commands/mspec-run.rb:76:in `options'
        	from /app/mspec-master/lib/mspec/utils/script.rb:286:in `main'
        	from mspec-master/bin/mspec-run:7:in `<main>'
        I, [2024-06-19T08:58:37.927905 #7]  INFO -- datadog: [datadog] DATADOG CONFIGURATION - CORE - {"date":"2024-06-19T08:58:37Z","os_name":"x86_64-pc-linux","version":"2.1.0","lang":"ruby","lang_version":"3.3.3","env":null,"service":"prof-correctness-scenarios/ruby_dir_interruption_patch","dd_version":null,"debug":false,"tags":null,"runtime_metrics_enabled":false,"vm":"ruby-3.3.3","health_metrics_enabled":false,"profiling_enabled":true}
--- FAIL: TestScenarios (19.35s)
```

...e.g. the monkey patches are missing.

For local testing, you can tweak the `gems.rb` to pick up the new
branch:

```ruby
gem 'datadog', git: 'https://github.com/datadog/dd-trace-rb.git', branch: 'ivoanjo/prof-9342-dir-interruption-workaround'
```

and you'll see the test passing.

Furthermore, I've created a branch where I introduce a bug in
`Dir.home`:

```ruby
gem 'datadog', git: 'https://github.com/datadog/dd-trace-rb.git',  branch: 'ivoanjo/prof-9342-dir-interruption-workaround-deleteme'
```

and here's the Ruby test suite flagging this behavior issue:

```
$ TEST_RUN_SECS=5 TEST_SCENARIOS="ruby_dir_interruption_patch" go test -v -run TestScenarios
=== RUN   TestScenarios
    correctness_test.go:210: Considering only scenarios in ruby_dir_interruption_patch
    correctness_test.go:225: Extract base image from: scenarios/ruby_dir_interruption_patch/Dockerfile
=== RUN   TestScenarios/scenarios/ruby_dir_interruption_patch
    correctness_test.go:244: Folder: scenarios/ruby_dir_interruption_patch
    correctness_test.go:245: Json file: scenarios/ruby_dir_interruption_patch/expected_profile.json
    correctness_test.go:246: Docker file: scenarios/ruby_dir_interruption_patch/Dockerfile
    correctness_test.go:248: Built test app with: test-app
    correctness_test.go:137: Running docker command with output /home/ivo.anjo/datadog/prof-correctness/data/ruby_dir_interruption_patch-1872402346
    correctness_test.go:138: '[/bin/sh -c bundle exec ddprofrb exec ruby mspec-master/bin/mspec-run --config mspec_config.rb spec-master/core/dir/]'
    correctness_test.go:151: Error running the test docker run -v /home/ivo.anjo/datadog/prof-correctness/data/ruby_dir_interruption_patch-1872402346:/app/data:rw -u 1000:1000 --security-opt seccomp=unconfined -e EXECUTION_TIME_SEC=5 -e DD_SERVICE=prof-correctness-scenarios/ruby_dir_interruption_patch test-app:latest - I, [2024-06-19T09:04:55.521052 #7]  INFO -- datadog: [datadog] DATADOG CONFIGURATION - CORE - {"date":"2024-06-19T09:04:55Z","os_name":"x86_64-pc-linux","version":"2.1.0","lang":"ruby","lang_version":"3.3.3","env":null,"service":"prof-correctness-scenarios/ruby_dir_interruption_patch","dd_version":null,"debug":false,"tags":null,"runtime_metrics_enabled":false,"vm":"ruby-3.3.3","health_metrics_enabled":false,"profiling_enabled":true}
        Dir interruption patch is present!
        ruby 3.3.3 (2024-06-12 revision f1c7b6f435) [x86_64-linux]
        ...................................................................................................................................................................................................................................................................FFEEFFEF...............................................................

        1)
        Dir.home when called without arguments returns the current user's home directory, reading $HOME first FAILED
        Expected nil == "/rubyspec_home"
        to be truthy but was false
        /app/spec-master/core/dir/home_spec.rb:16:in `block (3 levels) in <top (required)>'
        /app/spec-master/core/dir/home_spec.rb:4:in `<top (required)>'

        2)
        Dir.home when called without arguments returns a non-frozen string FAILED
        Expected nil.frozen?
        to be falsy but was true
        /app/spec-master/core/dir/home_spec.rb:20:in `block (3 levels) in <top (required)>'
        /app/spec-master/core/dir/home_spec.rb:4:in `<top (required)>'

        (...etc...)

        32 files, 330 examples, 440 expectations, 5 failures, 3 errors, 0 tagged
--- FAIL: TestScenarios (19.42s)
```

…uby-spec