Reads config path from environment variable CLOEEPY_CONFIG_PATH
        and sets as instance attr

def _set_config_path(self):
        """
        Reads config path from environment variable CLOEEPY_CONFIG_PATH
        and sets as instance attr
        """
        self._path = os.getenv("CLOEEPY_CONFIG_PATH")
        if self._path is None:
            msg = "CLOEEPY_CONFIG_PATH is not set. Exiting..."
            sys.exit(msg)