[Python o11y] Fix Python O11Y artifacts name (#35965)
Update observability to PYPI failed because the artifact name is not correct.
This PR:
* Fix the artifacts name.
* Add step to test observability artifacts in `test_packages.sh`.
* Added `-fno-ipa-cp` compile flag.
* We're seeing `inlining failed in call to always_inline 'vsnprintf': function body can be overwritten at link time` errors when building from source using musl libc.
* Based on [investigation](https://gitlab.alpinelinux.org/alpine/aports/-/issues/8626), it's because we're using `-flto` flag.
* One solution is to [disable fortify by adding this flag](https://gitlab.alpinelinux.org/alpine/aports/-/issues/8626).
After this PR, the observability artifacts have the correct name:
* [Distribution Tests Python Linux](https://pantheon.corp.google.com/storage/browser/grpc-testing-kokoro-prod/test_result_public/prod/grpc/core/pull_request/linux/grpc_distribtests_python/28687/20240223-105306/github/grpc/artifacts;tab=objects?pageState=(%22StorageObjectListTable%22:(%22f%22:%22%255B%255D%22))&e=13802955&mods=-logs_tg_prod&prefix=&forceOnObjectsSortingFiltering=false)
Also tested that the artifacts build in this PR can be successfully uploaded to testpypi:
* https://test.pypi.org/project/grpcio-observability/1.63.0.dev0
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Closes #35965
PiperOrigin-RevId: 611268154
Xuan Wang
9b424b5dd4