Install the repository hook for this repo.

        Args:
            hook_name (str)
            hook_content (str)

def install_hook(self, hook_name, hook_content):
        """Install the repository hook for this repo.

        Args:
            hook_name (str)
            hook_content (str)
        """
        hook_path = os.path.join(self.path, '.git/hooks', hook_name)
        with open(hook_path, 'w') as f:
            f.write(hook_content)
        os.chmod(hook_path, stat.S_IEXEC | stat.S_IREAD | stat.S_IWRITE)