Replace $( document ).ready(...) by $(...)

In jQuery 3 $(document).ready(...) is deprecated.
https://jquery.com/upgrade-guide/3.0/#deprecated-document-ready-handlers-other-than-jquery-function

Change-Id: I1a9f578d8cf8fa2d9dd38a1b2d3a0b3c32914b74

resources/js/ext.uls.interface.js

@@ -523,6 +523,6 @@
 	if ( document.readyState === 'interactive' ) {
 		init();
 	} else {
-		$( document ).ready( init );
+		$( init );
 	}
 }( jQuery, mediaWiki ) );