Fix removing item twice

Add spec which is fixed with this commit.

In the `sTagsArea` zone there are two elements with the same `data-val`:
the `<span class="amsify-select-tag>` containing the selected tag and
the `<li class="amsify-list-item" data-val="1">` containing the
suggested tag.

This means every time we call `removeTag`, the `removeTagByItem`
function is called twice, and might remove extra items.

Suggested PR:
c8765a6915

vendor/assets/javascripts/jquery.amsify.suggestags.js

@@ -626,7 +626,7 @@ var AmsifySuggestags;
 
 		removeTag: function(value, animate=true) {
 			var _self = this;
-			$findTags = $(this.selectors.sTagsArea).find('[data-val="'+value+'"]');
+			$findTags = $(this.selectors.inputArea).find('[data-val="'+value+'"]');
 			if($findTags.length) {
 				$findTags.each(function(){
 					_self.removeTagByItem(this, animate);