Checkout to a specific commit.

    If commit is None then checkout to master.

def checkout_commit(repo_path: str,
                    commit: Any = None) -> None:  # pylint:disable=redefined-outer-name
    """Checkout to a specific commit.

    If commit is None then checkout to master.
    """
    commit = commit or 'master'
    run_command(cmd='git checkout {}'.format(commit), data=None, location=repo_path, chw=True)