Add 'Test API' entry for RESTful API testing

[2025testapi]

Added a new entry for 'Test API' with details for RESTful API testing.

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Summary by cubic

Added "Test API" to the resources list to provide a Postman alternative for browser-based REST API testing. Includes the Developer Tools category, Chrome Web Store URL, and keywords for easy discovery.

^{Written for commit 5c6bdad. Summary will update automatically on new commits.}

[github-actions]

New resource link: https://chromewebstore.google.com/detail/test-api/bkndipmbnodeicgpmldococoiolcoicg

[cubic-dev-ai]

No issues found across 1 file