git rename branch

change global default branch to main:

# from now on everytime `git init` is run, the default branch is what's configured
git config --global init.defaultBranch <new-default-branch-name>
# make default branch main
git config --global init.defaultBranch main

change repository branch name:

# rename branch
git branch -m master main
# updates branch for push
git push origin :master main
# allows for pushing changes to remote
git branch --set-upstream-to=origin/main main