🧪 [testing improvement] Add test for case-insensitive hostname matching

[rowan-m]

🎯 What: The testing gap addressed was the lack of a test case for case-insensitive hostname verification in the ReCaptcha class.
📊 Coverage: The new test testVerifyHostnameMatchCaseInsensitive covers scenarios where the expected hostname and the response hostname have different casing (e.g., 'HOST.NAME' vs 'host.name' and vice versa).
✨ Result: This improvement ensures that the case-insensitive matching behavior is preserved during future refactoring and increases the reliability of the hostname validation logic.

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PR created automatically by Jules for task 5612976521281188627 started by @rowan-m

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[coveralls]

coverage: 100.0%. remained the same
when pulling a7a276e on testing-improvement-hostname-case-insensitive-5612976521281188627
into a6c5041 on main.