fix: fixing test requirements

[papriwal]

Issue #, if available:

Description of changes:
Fix Python 3.9 tox failure due to google-re2 missing prebuilt wheels. The google-re2 package is transitive dependancy.

• Latest google-re2 versions lack Python 3.9 wheels
• Forces source compilation requiring Bazel (not available in CI)
• Added constraint: google-re2<1.1.20250805; python_version<"3.10"
• Only affects Python 3.9, allows latest versions on 3.10+

Testing done:

• Reproduced failure locally with tox -e py39
• Verified fix resolves build error
• Confirmed constraint only applies to Python 3.9
• Tox command completes successfully

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