Make wonky `--watch` tests pass on native Mac OS CI

[Gedochao]

Created from a comment by @tgodzik in #2515 (comment)

RunTestsDefault.watch artifacts & BloopTests.Restart Bloop server while watching were intermittently failing on native Mac OS CI (and thus blocking it, as 5+ restarts were required for each job), so they are currently disabled for that particular setup (they're still being run for native Linux, native Windows and JVM).

We need to figure out why they fail on Mac in particular and re-enable them there.

Note: I was not able to replicate the problems on my local Mac, the issue seems to only occur on our CI

[Gedochao]

This now applies to most tests in scala.cli.integration.RunWithWatchTestDefinitions (appropriate TODO comments are in place).
Also see:

• NIT Refactor existing --watch tests #3175
• Fix --watch to work correctly with changing using directives & sources requiring code generation (scripts, markdown, etc) #3218
• Ensure resource directories passed via a using directive aren't ignored in --watch mode #3221