Add unit tests for got_mod_rewrite() in src/wp-admin/includes/misc.php

[pbearne]

Reference: https://core.trac.wordpress.org/ticket/65134

This PR adds comprehensive unit tests for the got_mod_rewrite() function in src/wp-admin/includes/misc.php.
The tests cover:

• Default behaviour based on Apache module detection.
• Overriding behaviour using the got_rewrite filter.

Trac ticket: https://core.trac.wordpress.org/ticket/65134

Use of AI Tools

AI assistance: Yes
Tool(s): Junie (JetBrains)
Model(s): gemini-3-flash-preview
Used for: Identifying untested functions, generating the test skeleton, and implementing the dataProvider logic. All code was reviewed and verified against WordPress core testing patterns.

[github-actions]

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[github-actions]

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