def clear(self, target_commit):
self.run('<STR_LIT>', '<STR_LIT>', target_commit)<EOL>self.run('<STR_LIT>', '<STR_LIT>')<EOL>
Resets the repository to the target commit, removing any staged,
        unstaged, and untracked files.

        Args:
            target_commit (str): the commit ID
        Raises:
            CommandError - if the commit does not exist