Coding Standards: Fix WPCS issue in [46107].

See #46631.

git-svn-id: https://develop.svn.wordpress.org/trunk@46108 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/tests/functions/getStatusHeaderDesc.php

@@ -32,7 +32,7 @@ public function _status_strings() {
 			array( 500, 'Internal Server Error' ),
 
 			// A string to make sure that the absint() is working.
-			array( "200", 'OK' ),
+			array( '200', 'OK' ),
 
 			// Not recognized codes return empty strings.
 			array( 9999, '' ),