git symbolic-ref refs/remotes/origin/HEAD refs/remotes/origin/main
Steps
Step 1 – Move the master branch to 'main'
Step 2 – Push 'main' to remote repo.
Step 3 – Point HEAD to 'main' branch.
Step 4 – Change default branch to 'main' on GitHub site.
Step 5 – Delete 'master' branch on the remote repo.