Rename local and remote Git branch names

git-branch-rename.sh

# rename
git branch -m new-name # option 1: when renaming the current branch
git branch -m <current_branch_name> <new_branch_name> # option 2: when renaming another branch

# delete old branch
git push origin -d <old_branch_name> # option 1
git push origin :<old_branch_name> # option 2 (shorter)

# unset upstream
git branch --unset-upstream <new_branch_name>

# push remote
git push origin <new_branch_name>
git push oirign -u <new_branch_name>