corrected issue when setting up chess engine variable

utils/dependencies_checker.py

@@ -25,7 +25,8 @@ def find_stockfish_path():
 
 
 def check_dependencies():
-    if os.getenv("CHESS_ENGINE_PATH") is None:
+    chess_engine_path =os.getenv("CHESS_ENGINE_PATH", "")
+    if chess_engine_path is None:
         stockfish_path = find_stockfish_path()
         if stockfish_path:
             print(f"Found Stockfish at: {stockfish_path}")
@@ -33,4 +34,4 @@ def check_dependencies():
         else:
             print("Stockfish not found!")
     else:
-        print(f"Stockfish already set to {os.getenv("CHESS_ENGINE_PATH")}")
+        print(f"Stockfish already set to {chess_engine_path}")