Request for Documentation: Deprecate old guidance on how to add plugins to community

[matterdoc]

Mattermost user lev.brouk from https://community-daily.mattermost.com has requested the following be documented:

Asking here (as per https://developers.mattermost.com/extend/plugins/community_process/ ) to begin the process to get a plugin added to community: https://github.com/mkraft/mattermost-plugin-whentochat

See the original post here.

This issue was generated from Mattermost using the Doc Up plugin.

[hanzei]

@levb What exactly needs up the updated in our docs?

[cwarnermm]

@levb - Can you provide some additional context for this documentation request, please?