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
Certain traps can't be supported on WASI, such as expectations for crashes, `setjmp` use, dynamic linking, multi-threading etc. These tests are marked as `UNSUPPORTED` when targeting Wasm/WASI.
Some tests are limited to only Linux, when they should also pass for
Android.
Additionally, InputStream.swift.gyb was disabled for Android ARMv7, but
wasn't for Android AArch64, which allow me to find the error on it and
fix it on #24521.
Finally, StringLowercasedUppercased is interesting in Android because it
checks the used ICU is correct for performing the tasks that the stdlib
needs.
