chore: move blacklisted symbol test to a bundled wheel

[mayeut]

cherry-picked from #703 to ensure the test will be kept when dropping Python 3.10
Pre-build wheel used for blacklisted symbol test and move the test to test_bundled_wheels.py

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.01%. Comparing base (967aaea) to head (ecd250b).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #707      +/-   ##
==========================================
+ Coverage   95.91%   96.01%   +0.10%     
==========================================
  Files          23       23              
  Lines        1981     1981              
  Branches      374      374              
==========================================
+ Hits         1900     1902       +2     
+ Misses         46       45       -1     
+ Partials       35       34       -1     

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[Copilot]

Pull request overview

This PR moves the zlib blacklisted-symbol integration test from an on-the-fly built extension (tests/integration/testzlib/*) into a prebuilt, bundled wheel and rehomes the test logic into test_bundled_wheels.py, so the test remains available when Python 3.10 is dropped.

Changes:

• Remove the in-repo testzlib extension source and build configuration used to generate the wheel during tests.
• Remove the container-based test_zlib_blacklist integration test from test_manylinux.py.
• Add a new bundled-wheel based blacklist-symbol test to tests/integration/test_bundled_wheels.py and commit the prebuilt wheel artifact.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/integration/testzlib/testzlib.c	Removes the C extension source previously compiled during integration tests.
tests/integration/testzlib/setup.py	Removes setuptools build script for the testzlib test extension.
tests/integration/testzlib/pyproject.toml	Removes build-system metadata for building the testzlib wheel.
tests/integration/test_manylinux.py	Removes the container-based zlib blacklist integration test.
tests/integration/test_bundled_wheels.py	Adds a new test that uses a bundled testzlib wheel to validate blacklist detection/reporting.

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