add dequeue test in priority queue

Author: hadis98

Diff for: Binary Heaps/priorityQueues.js

@@ -24,4 +24,6 @@ priorityQueue.enqueue('U', 3);
 priorityQueue.enqueue('W', 9);
 priorityQueue.enqueue('P', 8);
 priorityQueue.enqueue('Z', 2);
-console.log(priorityQueue.values);
+console.log(priorityQueue.values);
+priorityQueue.dequeue();
+console.log(priorityQueue.values); //delete the element with smallest priority