[Commands] Register context menu even if command in group

[BlackLotusLV]

Description

Allow to register ContextMenu command withing a command group. Currently if you set applicationCommandType to (user/message)ContextMenu, it will not register it as a context menu, if it is under a group. While they do not support being grouped, they should still register under the same name to reduce the need to have duplicate code.

This was a thing in the old slash commands extension. It didn't care if the context menu was placed in a group or not, it simply registered it of its own name.

Specify the libraries you want this feature request to affect

DSharpPlus.Commands

Other considerations

No response