Have CollectOSS declare (via a user agent header) itself in API calls to github

I suspect we arent currently doing this and it might help github identify traffic from our tooling (so we pass through bot detection better and/or so someone at github can report issues to us if we need to tweak the way we hit github's API).

This might be a good "challenging first issue" for someone

I think the user agent we pick should include:
- project name (CollectOSS)
- maybe a mention of CHAOSS/Linux foundation
- a link to this github repo
- ideally also the version number of CollectOSS