Add a helpful warning for links that don't point anywhere.

comfy_extras/nodes_canny.py

-#From https://github.com/kornia/kornia
 import math
 
 import torch

folder_paths.py

@@ -181,6 +181,8 @@ def get_full_path(folder_name, filename):
         full_path = os.path.join(x, filename)
         if os.path.isfile(full_path):
             return full_path
+        elif os.path.islink(full_path):
+            logging.warning("WARNING path {} exists but doesn't link anywhere, skipping.".format(full_path))
 
     return None