[lint] Rename exception variables to exc

Use the more explicit (and common) exc instead of e as the variable
holding the exception in except handlers.

discord/ext/commands/converter.py

@@ -343,8 +343,8 @@ class InviteConverter(Converter):
         try:
             invite = await ctx.bot.get_invite(argument)
             return invite
-        except Exception as e:
-            raise BadArgument('Invite is invalid or expired') from e
+        except Exception as exc:
+            raise BadArgument('Invite is invalid or expired') from exc
 
 class EmojiConverter(IDConverter):
     """Converts to a :class:`Emoji`.