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: Iff3d7fb07a739fc6ff9b62a2f586c54cd9c8f315

modules/ext.echo.init.js

@@ -14,7 +14,7 @@
 	mw.echo.config.maxPrioritizedActions = 2;
 
 	// Activate ooui
-	$( document ).ready( function () {
+	$( function () {
 		var myWidget, echoApi,
 			$existingAlertLink = $( '#pt-notifications-alert a' ),
 			$existingMessageLink = $( '#pt-notifications-notice a' ),

modules/special/ext.echo.special.js

@@ -4,7 +4,7 @@
 	/*!
 	 * Echo Special:Notifications page initialization
 	 */
-	$( document ).ready( function () {
+	$( function () {
 		var specialPageContainer,
 			limitNotifications = 50,
 			links = mw.config.get( 'wgNotificationsSpecialPageLinks' ),