Fix graph reverse method

Author: itsamirhn

src/data-structures/graph/Graph.js

@@ -138,14 +138,19 @@ export default class Graph {
    */
   reverse() {
     /** @param {GraphEdge} edge */
+    const reversedEdges = [];
     this.getAllEdges().forEach((edge) => {
       // Delete straight edge from graph and from vertices.
       this.deleteEdge(edge);
 
       // Reverse the edge.
       edge.reverse();
 
-      // Add reversed edge back to the graph and its vertices.
+      // Add reversed edge to the list of reversed edges.
+      reversedEdges.push(edge);
+    });
+    reversedEdges.forEach((edge) => {
+      // Add reversed edge to the graph.
       this.addEdge(edge);
     });