fix(ci): resolve webhook IP cache invalidation bug

[MrButtCode]

[FIX] resolve webhook IP cache invalidation bug

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Resolves a critical performance bug in the webhook IP validation logic.

In utility.py the cached_load_time variable was declared locally strictly inside cache_has_expired(). This caused the timestamp to reset to the 1970 epoch on every single function call. As a result the expiration check always evaluated to True forcing the application to make a syncronous HTTP request to the GitHub API on every incoming webhook instead of using the cached IP blocks.

The Fix:
Elevated cached_load_time to module level scope and updated get_cached_web_hook_blocks() to reset the timestamp to datetime.now() only after a successful GitHub API fetch. This restores the intended 1 hour caching behavior.

Additionally refactored the caching architecture per maintainer review:

• Made cache_has_expired a pure function that accepts the load time as an explicit argument.
• Removed all test bypasses and mocks from the production environment.
• Achieved full test isolation by directly reseting the module state in the BaseTestCase setUp method.

This ensures the production code remains completely free of test specific logic while keeping the CI pipeline perfectly stable.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud