Auto-Delete branch after successful deploy

[sachioross]

THIS HAS TWO OPTIONS:

1. Track the branches that have been deployed and run a scheduled auto-deletion (this could allow for notification and stopping of this action in the event that we need to troubleshoot)
2. Alternatively: if publish action is successful, then auto-delete branch to keep repo clean and prevent conflicts from future contribution by same repository (challenge: once deleted, it's gone)