[build] Improve test parallelism through custom resource for socket tests

[fhanau]

So far these tests were all running sequentially after all other tests, now we can run one of them at a time alongside other tests. This should make CI slightly faster.

Reviewers: This will require a downstream change so that the downstream build knows to limit the resource. It will also unlock some exciting optimizations there, stay tuned.

I have confirmed locally that this works as intended.

[ask-bonk]

The diff confirms all four test changes are straightforward exclusive -> resources:socket:1 replacements. The tail-worker-test at line 76 already had exclusive (it was one of the four).

This is a clean, well-motivated change. The approach is correct:

• Custom Bazel resources (--local_resources=socket=1 + resources:socket:1 tag) provide mutual exclusion among socket-using tests while allowing non-socket tests to run in parallel.
• All four previously-exclusive tests are converted.
• No remaining exclusive tags exist in the source tree.
• The comment on the first occurrence clearly explains the rationale.
• The PR description notes the downstream dependency, which is appropriate.

There are no logic bugs, security issues, backward compat violations, or correctness problems.

LGTM

github run

[npaun]

Really cool trick. How did you come up with it?

[fhanau]

Really cool trick. How did you come up with it?

Reading the bazel command line reference and release notes – I think this has been supported since Bazel 7, I just never figured out the right syntax for it