Enable GitHub Project

Today in the Weekly community call I mentioned the GitHub (GH) 'Project'
a new GH feature that allows for better tracking of those GH pull requests and issues cross the board. More info at Planning and tracking with Projects - GitHub Docs
and the respective change-log: projects Archives | The GitHub Blog

In short, I have added manually the majority of the issues and all PRs.
New views were also created with different filters to facilitate the triage of the issues and to avoid letting PRs waiting too long without review or a reviewer.

I have also added 2 new GH actions (yml) that automatically add new
PRs and issues into the project. These two new files are located at online/.github/workflows at master · CollaboraOnline/online · GitHub

And finally I have set different project workflows that automatically set item status based on the GH trigger (open, closed, code changes requested, code review approved) Collabora Online · GitHub

Mentioned Collabora Online Weekly: #108