Fix array index out of bounds on enter key event zurb#773

Author: SrPatinhas

src/TributeEvents.js

@@ -228,7 +228,8 @@ class TributeEvents {
       },
       enter: (e, el) => {
         // choose selection
-        if (this.tribute.isActive && this.tribute.current.filteredItems) {
+        const filteredItems = this.tribute.current.filteredItems;
+        if (this.tribute.isActive && filteredItems && filteredItems.length) {
           e.preventDefault();
           e.stopPropagation();
           setTimeout(() => {