Use exact array-element membership (.some((h) => h === host)) instead of Array.prototype.includes() in the MITM hosts unit test, so CodeQL's js/incomplete-url-substring-sanitization heuristic does not misread an Array.includes membership check as a String.includes URL-substring test. Functionally identical. Mirrors #4386 (already merged into release/v3.8.31). Closes the only open code-scanning alert (#660).