Adds a branch name check to CircleCI
Adds a branch name check to CircleCI

Since the default git branch has changed to 'main', reintroducing a
branch named 'master' could accidentally break things, like GitHub's
automatic link updates. This change attempts to make reintroducing a
'master' branch more difficult, by failing CI if such a branch exists.

samvera/hyrax,samvera/hyrax,samvera/hyrax,samvera/hyrax