Cherry-pick of #83128, #82399, and #82878, merged as ea6ca2b5db, 0c4e56174b, and e34eb3331f respectively.
**Explanation**: Currently `test/CMakeLists.txt` can only set `SWIFT_LIT_ARGS` for all tests uniformly. This means that we can't have tests for Embedded Swift with a different set of `lit.py` arguments.
Also, create new `check-swift-embedded-wasi` target from `test/CMakeLists.txt`, tweak `lit.cfg` to support WASI Clang resource dir, exclude unsupported tests based on `CPU=wasm32` instead of `OS=wasi`.
**Scope**: Limited to Embedded Swift test suite.
**Risk**: Low, due to limited scope.
**Testing**: #82878 was incubated on `main` for 2 weeks, #82399 for 3 weeks with no disruption, #83128 merged this week, but enables all these tests on CI, which are consistently passing.
**Issue**: rdar://156585717
**Reviewer**: @bnbarham
Instead, use the `%target-swift-5.1-abi-triple` substitution to compile the tests
for deployment to the minimum OS versions required for use of _Concurrency APIs.
The 5.5/5.6 concurrency runtime in the concurrency backdeploy library
just doesn't have the pieces necessary to emit the desired error
message. Disabling it in that environment.
Commit afc5116ef0 added the support to track re-used continuations.
* Enable running tests from test/Concurrency/ directory in freestanding/minimal presets
* Mark failing Concurrency tests as XFAIL/SKIP on freestanding/minimal