Extra links supported for operators coming from third-party packages:

airflow.serialization.serialized_objects.BUILTIN_OPERATOR_EXTRA_LINKS

airflow/cli/cli_parser.py
name='test',
        help="Execute one single DagRun",
        description=(
            "Execute one single DagRun for a given DAG and execution date, "
            "using the DebugExecutor.\n"
            "\n"
            "The --imgcat-dagrun option only works in iTerm.\n"
            "\n"
            "For more information, see: https://www.iterm2.com/documentation-images.html\n"
            "\n"
            "If --save-dagrun is used, then, after completing the backfill, saves the diagram "
            "for current DAG Run to the indicated file.\n"
            "The file format is determined by the file extension. "
            "For more information about supported format, "
            "see: https://www.graphviz.org/doc/info/output.html\n"
            "\n"
            "If you want to create a PNG file then you should execute the following command:\n"
            "airflow dags test <DAG_ID> <EXECUTION_DATE> --save-dagrun output.png\n"
            "\n"
            "If you want to create a DOT file then you should execute the following command:\n"
            "airflow dags test <DAG_ID> <EXECUTION_DATE> --save-dagrun output.dot\n"
        ),
        func=lazy_load_command('airflow.cli.commands.dag_command.dag_test'),
        args=(
            ARG_DAG_ID,
            ARG_EXECUTION_DATE,
            ARG_SUBDIR,
            ARG_SHOW_DAGRUN,
            ARG_IMGCAT_DAGRUN,
            ARG_SAVE_DAGRUN,