Change a container's deploy branch without recreating it

What's new

• Each linked repository now has an Edit button next to its watched branch, in the project's Repositories tab.
• Point a container at a different branch, for example to promote a feature branch to production, no need to delete and recreate the container.
• This only changes which future pushes trigger a deploy: it does not redeploy the container that is currently running. Trigger one afterward with a push on the new branch, or with the container's Build button.