fix another link

Author: matsumotosan

src/lightning/fabric/utilities/cloud_io.py

@@ -45,7 +45,7 @@ def _load(
             types. If loading a checkpoint from a trusted source that contains an ``nn.Module``, use
             ``weights_only=False``. If loading checkpoint from an untrusted source, we recommend using
             ``weights_only=True``. For more information, please refer to the
-            `PyTorch Developer Notes on Serialization Semantics <https://docs.pytorch.org/docs/main/notes/serialization.html#id3>`__.
+            `PyTorch Developer Notes on Serialization Semantics <https://docs.pytorch.org/docs/main/notes/serialization.html#id3>`_.
 
     """
     if not isinstance(path_or_url, (str, Path)):