Correct reference to 'self' variable

It doesn't exist in this scope so the 'self' in
the scope above was being referenced instead,
preventing it from erroring.

app/assets/javascripts/stick-to-window-when-scrolling.js

@@ -263,7 +263,7 @@
         $(window).scrollTop(this.getInPageEdgePosition(sticky) - windowHeight);
       }
 
-      self.hasResized = false;
+      this.hasResized = false;
     },
     releaseEl: function (el, sticky) {
       el.$fixedEl.css(sticky.edge, '');