Fix `git bdm` (branch delete merged) selection
Fix `git bdm` (branch delete merged) selection

Don't delete any branches without slashes in their names.  (e.g. our
normal stages: `dev`, `release-candidate`, and `master`)

nestukh/dotfiles,benizi/dotfiles,benizi/dotfiles,nestukh/dotfiles,nestukh/dotfiles,benizi/dotfiles,nestukh/dotfiles,benizi/dotfiles,benizi/dotfiles,benizi/dotfiles,nestukh/dotfiles,nestukh/dotfiles,benizi/dotfiles,benizi/dotfiles,nestukh/dotfiles,nestukh/dotfiles