[crashtracker] Add tests for unix socket receiver, and mark slow tests ignore

[danielsn]

What does this PR do?

• Adds an end-to-end test for the unix socket receiver for the crashtracker.
• Marks a slow test ignore

Motivation

• We didn't actually have testing for this yet, now we do.
• Testing the "release" version was more of a test-the-tests thing, don't actually need to do that regularly to get confidence in the underlying code.

Additional Notes

These tests pass a bunch of arguments positionally. This is not ideal, and made them harder to maintain, but since they're tests I felt leaving it that way was OK for now.

How to test the change?

This is a test!

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 1.92308% with 51 lines in your changes missing coverage. Please review.

Project coverage is 69.55%. Comparing base (41aebd2) to head (dd2df65).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #484      +/-   ##
==========================================
- Coverage   69.62%   69.55%   -0.07%     
==========================================
  Files         199      200       +1     
  Lines       26633    26656      +23     
==========================================
- Hits        18542    18541       -1     
- Misses       8091     8115      +24     

Components	Coverage Δ
crashtracker	17.20% <ø> (+0.02%)	⬆️
datadog-alloc	98.76% <ø> (ø)
data-pipeline	51.30% <ø> (ø)
data-pipeline-ffi	0.00% <ø> (ø)
ddcommon	85.97% <ø> (ø)
ddcommon-ffi	74.15% <ø> (ø)
ddtelemetry	56.37% <ø> (ø)
ipc	84.66% <ø> (ø)
profiling	79.14% <ø> (ø)
profiling-ffi	59.53% <ø> (ø)
serverless	0.00% <ø> (ø)
sidecar	36.26% <ø> (ø)
sidecar-ffi	0.00% <ø> (ø)
spawn-worker	54.98% <ø> (ø)
trace-mini-agent	69.36% <ø> (ø)
trace-normalization	97.79% <ø> (ø)
trace-obfuscation	95.73% <ø> (ø)
trace-protobuf	24.52% <ø> (ø)
trace-utils	90.79% <ø> (ø)