Document pip Discord channel

A link is provided to the PyPA Discord, rather than the specific
channel, because the former presents the user with an invite, but for
channel links I'm not sure how nice the process is for users who aren't
already part of the Discord.

The channel is only document under the development docs, since we want
to keep it focussed on questions around developing on the codebase, and
not move more general discussions from GitHub issues

Author: matthewhughes934

docs/html/development/index.rst

@@ -8,7 +8,8 @@ testing, and documentation.
 
 You can also join ``#pypa`` (general packaging discussion and user support) and
 ``#pypa-dev`` (discussion about development of packaging tools) `on Libera.chat`_,
-or the `distutils-sig mailing list`_, to ask questions or get involved.
+or the ``#pip`` channel on the `PyPA Discord`_, or the `distutils-sig mailing list`_,
+to ask questions or get involved.
 
 .. toctree::
     :maxdepth: 2
@@ -28,3 +29,4 @@ or the `distutils-sig mailing list`_, to ask questions or get involved.
 
 .. _`on Libera.chat`: https://kiwiirc.com/nextclient/#ircs://irc.libera.chat:+6697/pypa-dev
 .. _`distutils-sig mailing list`: https://mail.python.org/mailman3/lists/distutils-sig.python.org/
+.. _`PyPA Discord`: https://discord.gg/pypa