git branch -M

git branch -M

      With a -m or -M option, <oldbranch> will be renamed to <newbranch>. If <oldbranch> had a corresponding reflog, it is renamed to match <newbranch>, and a reflog entry is created to remember the branch
      renaming. If <newbranch> exists, -M must be used to force the rename to happen.

See also

• git branch, git: upstream, git branch --delete branch name, [ --list | -a | -r | -M ]