Remove TextChannel.default_thread_slowmode_delay

This doesn't have meaning on text channels apparently

discord/channel.py

@@ -160,10 +160,6 @@ class TextChannel(discord.abc.Messageable, discord.abc.GuildChannel, Hashable):
         The default auto archive duration in minutes for threads created in this channel.
 
         .. versionadded:: 2.0
-    default_thread_slowmode_delay: :class:`int`
-        The default slowmode delay in seconds for threads created in this channel.
-
-        .. versionadded:: 2.1
     """
 
     __slots__ = (
@@ -180,7 +176,6 @@ class TextChannel(discord.abc.Messageable, discord.abc.GuildChannel, Hashable):
         '_type',
         'last_message_id',
         'default_auto_archive_duration',
-        'default_thread_slowmode_delay',
     )
 
     def __init__(self, *, state: ConnectionState, guild: Guild, data: Union[TextChannelPayload, NewsChannelPayload]):
@@ -211,7 +206,6 @@ class TextChannel(discord.abc.Messageable, discord.abc.GuildChannel, Hashable):
         # Does this need coercion into `int`? No idea yet.
         self.slowmode_delay: int = data.get('rate_limit_per_user', 0)
         self.default_auto_archive_duration: ThreadArchiveDuration = data.get('default_auto_archive_duration', 1440)
-        self.default_thread_slowmode_delay: int = data.get('default_thread_rate_limit_per_user', 0)
         self._type: Literal[0, 5] = data.get('type', self._type)
         self.last_message_id: Optional[int] = utils._get_as_snowflake(data, 'last_message_id')
         self._fill_overwrites(data)
@@ -306,7 +300,6 @@ class TextChannel(discord.abc.Messageable, discord.abc.GuildChannel, Hashable):
         category: Optional[CategoryChannel] = ...,
         slowmode_delay: int = ...,
         default_auto_archive_duration: ThreadArchiveDuration = ...,
-        default_thread_slowmode_delay: int = ...,
         type: ChannelType = ...,
         overwrites: Mapping[OverwriteKeyT, PermissionOverwrite] = ...,
     ) -> TextChannel:
@@ -366,10 +359,6 @@ class TextChannel(discord.abc.Messageable, discord.abc.GuildChannel, Hashable):
             Must be one of ``60``, ``1440``, ``4320``, or ``10080``.
 
             .. versionadded:: 2.0
-        default_thread_slowmode_delay: :class:`int`
-            The new default slowmode delay in seconds for threads created in this channel.
-
-            .. versionadded:: 2.1
 
         Raises
         ------