docs: remove Skins in Extension docstring (#1559)

https://discord.com/channels/789032594456576001/1160026100001427476

Signed-off-by: Nathan Spees <[email protected]>

Author: Catalyst4222

interactions/models/internal/extension.py

@@ -22,7 +22,7 @@
 
 class Extension:
     """
-    A class that allows you to separate your commands and listeners into separate files. Skins require an entrypoint in the same file called `setup`, this function allows client to load the Extension.
+    A class that allows you to separate your commands and listeners into separate files. Extensions require an entrypoint in the same file called `setup`, this function allows client to load the Extension.
 
     ??? Hint "Example Usage:"
         ```python