ext.uls.eventlogger: Remove use of mw.eventLog.logEvent() promise

This change prevents a failure when clicking on the language revert
button.

This change is a follow-up to c578db020d.

Change-Id: Ic5da1b1dcdcc07de417a6eef0189940cb5a2392f

resources/js/ext.uls.eventlogger.js

@@ -61,7 +61,8 @@
 	 * @param {jQuery.Deferred} deferred
 	 */
 	function ulsLanguageRevert( deferred ) {
-		log( { action: 'ui-lang-revert' } ).always( deferred.resolve() );
+		log( { action: 'ui-lang-revert' } );
+		deferred.resolve();
 	}
 
 	/**