CI: Test schemes

[pblazej]

Let's try to separate on-device tests from the core suite (with proper retry, timeout, etc.).

[github-actions]

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[pblazej]

@hiroshihorie you can disable the device tests (ideally move them into a new plan called Device or sth) in spare time 🚀

If you encounter sth flaky, maybe it's worth to create a 3rd suite called Flaky for investigation.

Let's make it 🟢 then try to parallelize.

[pblazej]

Here's the status quo:

My plan is to move them to a separate target/filter out.

Unfortunately, test plans vs xcodebuild vs spm is a pain, no silver bullet here.
Moving to a separate test target is also an option (LiveKitTestsDevice etc.) but we need to extract test utils first.

[pblazej]

@hiroshihorie what I ended up doing:

• extracted common test utils into Tests/LiveKitTestSupport target
• split tests into 3 targets (Core/Audio (things that makes more sense on device)/ObjC)
• removed the default test plan - for SPM it does more harm than good
• enabled ALL Core + ObjC tests on CI
  • retry 2x
  • timeout total 10m
  • parallel (about 1.5x of speed up)

Let's see how flaky it is 🤞 Marking that as ready for review.

BTW I haven't touched the LKTestHost at all, if you've got any ideas for simplifying on-device testing, just let me know or push it in a separate PR.

[pblazej]

Added tsan/asan variants to the matrix