Don't turn off listening to reference clicks

For event logging purposes we need to be able to listen to reference and
backlink clicks. Clicks on these elements were disabled before this patch.

Although clicking on backlinks was disabled, it wasn't working properly
as the user could click on those links and be taken to the reference.
Thus this piece of code has been removed.

Bug: T191086
Change-Id: Idbaa39523a35f3b649f521be05c83255aa2b1396

resources/skins.minerva.scripts/references.js

@@ -102,12 +102,10 @@
 
 		if ( $refs.length ) {
 			$refs
-				.off( 'click' )
-				.on( 'click', {
+				.off( 'click.references' )
+				.on( 'click.references', {
 					page: page
 				}, onClickReference );
-			page.$( '.mw-cite-backlink a' )
-				.off( 'click' );
 		}
 	}