fix: add \_\_eq\_\_ in Node class

#8770

Author: JadeKim042386

Diff for: graphs/greedy_best_first.py

@@ -82,6 +82,9 @@ def calculate_heuristic(self) -> float:
 
     def __lt__(self, other) -> bool:
         return self.f_cost < other.f_cost
+    
+    def __eq__(self, other):
+        return self.pos == other.pos
 
 
 class GreedyBestFirst: