Add a "Do not ask again" checkbox to the branch dialog after a gerrit checkout.

There is this popup after checking out a commit from gerrit that always ask if I want to create a branch for the commit I just checked out. I never ever have used this functionality, but this message box always need some interaction. So it would be nice if you could just add a do not ask again checkbox to this dialog to make it permanently hidden for users that don't need that functionality.

We already have the class Utils::CheckableMessageBox that provides such functionality.