Docs: Remove links to Web Archive from source

Neither of the removed links is crucial; one of them refers to a site that has
since started being malicious; while the Web Archive links remain safe, some
scanners warn about such links. Removing them is the safest thing to do.

Fixes gh-4981
Closes gh-4991

(cherry picked from commit e24f2dcf3f)

src/attributes/prop.js

@@ -62,7 +62,6 @@ jQuery.extend( {
 				// Support: IE <=9 - 11 only
 				// elem.tabIndex doesn't always return the
 				// correct value when it hasn't been explicitly set
-				// https://web.archive.org/web/20141116233347/http://fluidproject.org/blog/2008/01/09/getting-setting-and-removing-tabindex-values-with-javascript/
 				// Use proper attribute retrieval(#12072)
 				var tabindex = jQuery.find.attr( elem, "tabindex" );
 

src/queue/delay.js

@@ -7,7 +7,6 @@ define( [
 "use strict";
 
 // Based off of the plugin by Clint Helfers, with permission.
-// https://web.archive.org/web/20100324014747/http://blindsignals.com/index.php/2009/07/jquery-delay/
 jQuery.fn.delay = function( time, type ) {
 	time = jQuery.fx ? jQuery.fx.speeds[ time ] || time : time;
 	type = type || "fx";