Fix various reference issues in documentation

Co-Authored-By: Riley Shaw <30989490+ShineyDev@users.noreply.github.com>

discord/ext/commands/errors.py

@@ -89,7 +89,7 @@ class CommandError(DiscordException):
 
     This exception and exceptions inherited from it are handled
     in a special way as they are caught and passed into a special event
-    from :class:`.Bot`\, :func:`on_command_error`.
+    from :class:`.Bot`\, :func:`.on_command_error`.
     """
     def __init__(self, message=None, *args):
         if message is not None:
@@ -457,7 +457,7 @@ class CommandOnCooldown(CommandError):
 
     Attributes
     -----------
-    cooldown: Cooldown
+    cooldown: ``Cooldown``
         A class with attributes ``rate``, ``per``, and ``type`` similar to
         the :func:`.cooldown` decorator.
     retry_after: :class:`float`
@@ -654,7 +654,7 @@ class BadUnionArgument(UserInputError):
     -----------
     param: :class:`inspect.Parameter`
         The parameter that failed being converted.
-    converters: Tuple[Type, ...]
+    converters: Tuple[Type, ``...``]
         A tuple of converters attempted in conversion, in order of failure.
     errors: List[:class:`CommandError`]
         A list of errors that were caught from failing the conversion.
@@ -692,7 +692,7 @@ class BadLiteralArgument(UserInputError):
     -----------
     param: :class:`inspect.Parameter`
         The parameter that failed being converted.
-    literals: Tuple[Any, ...]
+    literals: Tuple[Any, ``...``]
         A tuple of values compared against in conversion, in order of failure.
     errors: List[:class:`CommandError`]
         A list of errors that were caught from failing the conversion.