genpolicy: add crate-scoped integration test

[Redent0r]

Provides a test runner that generates a policy and validates it with canned requests. The initial set of test cases is mostly for illustration and will be expanded incrementally.

In order to enable both cross-compilation on Ubuntu test runners as well as native compilation on the Alpine tools builder, it is easiest to switch to the vendored openssl-src variant. This builds OpenSSL from source, which depends on Perl at build time.

Adding the test to the Makefile makes it execute in CI, on a variety of architectures. Building on ppc64le requires a newer version of the libz-ng-sys crate.

Fixes: kata-containers#10061

Merge Checklist

• Followed patch format from upstream recommendation: https://github.com/kata-containers/community/blob/main/CONTRIBUTING.md#patch-format
  • Included a single commit in a given PR - at least unless there are related commits and each makes sense as a change on its own.
• Aware about the PR to be merged using "create a merge commit" rather than "squash and merge" (or similar)
• The upstream/missing label (or upstream/not-needed) has been set on the PR.

Summary

todo:

• fix test failure
• downstream policy: add policy crate and add network namespace check to policy kata-containers/kata-containers#10613 once it's merged
• enable and require cargo test in github CI

Test Methodology