fix(tests): override core.hooksPath in test repos to prevent bypass

[google-labs-jules]

What:
Set core.hooksPath to .git/hooks locally when initializing temporary git repositories in test_hooks.py.

Why:
The test HooksTests.test_end_to_end_post_commit_runs fails in environments where a global core.hooksPath configuration (e.g., set to /dev/null or by tools like pre-commit) bypasses the local hooks execution. By overriding it locally for the test repositories, we guarantee that the installed hook gets triggered as expected during git commit, stabilizing the test regardless of host configuration.

Risk:
Low. The change only impacts the setup of temporary test repositories within tests/test_hooks.py. It does not affect production code or external repositories.

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PR created automatically by Jules for task 4906147748027970433 started by @raccioly

[google-labs-jules]

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