* Drop Fedora 33
By the time we release, it's going to reach EOL.
* Drop Raspberry Pi OS 10, add support for 11
* Bring RPi OS 10 back
* Add Alma Linux 8
* Fix-up RHEL EOL dates
* Add '(Legacy)' to Raspberry Pi OS 10
* Drop CentOS 8
Vendor `discord.ext.menus` from commit `cc108bed812d0e481a628ca573c2eeeca9226b42` at https://github.com/Rapptz/discord-ext-menus
Co-authored-by: jack1142 <6032823+jack1142@users.noreply.github.com>