Add a step in distribution test which checks if any of the artifacts exceeds 80 MB since Pypi has a per-file size limit.
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Closes#35831
COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35831 from XuanWang-Amos:dist_test_add_size_check de50f20e14
PiperOrigin-RevId: 605664419
* cleanup C# win artifact build
* build C# basictests on win with ninja
* specify default parallelism for C# win artifact
* honor GRPC_PYTHON_BUILD_EXT_COMPILER_JOBS in build_artifact_python.bat
* set --inner_jobs for windows grpc_build_artifact job
* fixup C# build picking env variables from C core build
* get rid of no longer needed NativeDependenciesConfiguration C# setting
* support "move and respawn" for kokoro jobs
* delete_nonartifacts.sh no longer needed
* bazel distribtest dont publish any artifacts
* try the altsrc respawn for selected jobs
* use altsrc for all windows CI jobs
* use altsrc for all macos CI jobs
* only move files under src/github
* fix uploading artifacts on windows
* Download the working msys64 and use it to compile 27
* Remove the cygwin detection override logic
* Only install Python interpreters in jobs running on winserver2016
* Fix the batch script substring check
* Increase the timeout for related jobs
* TIL that there is an allow list for Kokoro env vars
* Download the working msys64 and use it to compile 27
* Remove the cygwin detection override logic
* Only install Python interpreters in jobs running on winserver2016
* Fix the batch script substring check
* Increase the timeout for related jobs
* TIL that there is an allow list for Kokoro env vars