Separate pending requests into separate channels depending on project

[violine1101]

The Problem

Currently all requests from the #other-requests channel are forwarded into the #other-pending-requests channel. When resolving requests there, you cannot easily focus on resolving bug reports for one specific project.

Possible Solution

Create separate pending-requests channels for "web", "mcl", "bds", and "realms". The bot could filter the request to the correct channel so we would not have to have separate incoming channels.