Editing non-master branches with the pencil icon doesn't work
Steps to reproduce:
- Go to the home page of the User Guide 4.6 edition https://docs.civicrm.org/user/en/4.6/
- Hover over the pencil icon at the top right of the page
- Expect the URL to be https://github.com/civicrm/civicrm-user-guide/edit/4.6/docs/index.md
- Observe the URL to be https://github.com/civicrm/civicrm-user-guide/edit/master/docs/index.md