feat(repo_settings/build): approve build mechanism and related repo settings

[ecrupper]

Repo settings page (a little wordy... open to suggestions):

Approve Build Look:

I decided to remove the Restart button whenever a build is in a pending approval state as well.

[wass3rw3rk]

the verbiage on the settings page doesn't mention "Fork" at all. I think we want to differentiate between regular PRs and Fork PRs here, no?

[ecrupper]

the verbiage on the settings page doesn't mention "Fork" at all. I think we want to differentiate between regular PRs and Fork PRs here, no?

I was thinking that "outside contributors" was somewhat covering that, but I can mention forks specifically

[wass3rw3rk]

yea.. wanted to close the gap from "outside contributors" -> "fork". it can get a little wishy washy with collaborator/contributor terminology, too. @wass3r is an "external collaborator" but can create non-forked branches, for example. i think "fork" is pretty common terminology that will add more clarity.

thanks for the edit.

[KellyMerrick]

lgtm