Airflow v2.0b3
 Kubernetes v1.19.3

Discovered issue while testing KubernetesPodOperator (haven't tested with other operator).
If I create a multiline string using """ """", add some variables inside (Jinja templating), then use this string as an argument to KubernetesPodOperator:
- In Graph View DAG is not visible (just gray area where it should be a digraph);
- in browser's web console i see the following error:

`Uncaught TypeError: node is undefined
    preProcessGraph http://localhost:8080/static/dist/dagre-d3.min.js:103
    preProcessGraph http://localhost:8080/static/dist/dagre-d3.min.js:103
    fn http://localhost:8080/static/dist/dagre-d3.min.js:103
    call http://localhost:8080/static/dist/d3.min.js:3
    draw http://localhost:8080/graph?dag_id=mydag&execution_date=mydate
    expand_group http://localhost:8080/graph?dag_id=mydag&execution_date=mydate
    <anonymous> http://localhost:8080/graph?dag_id=mydag&execution_date=mydate`

Tree view works without issues in this case. The DAG succeeds.
airflow/models/baseoperator.py
wait_for_downstream: bool = False,
        dag=None,
        params: Optional[Dict] = None,
        default_args: Optional[Dict] = None,  
        priority_weight: int = 1,
        weight_rule: str = WeightRule.DOWNSTREAM,
        queue: str = conf.get('celery', 'default_queue'),
        pool: Optional[str] = None,
        pool_slots: int = 1,
        sla: Optional[timedelta] = None,
        execution_timeout: Optional[timedelta] = None,
        on_execute_callback: Optional[TaskStateChangeCallback] = None,
        on_failure_callback: Optional[TaskStateChangeCallback] = None,
        on_success_callback: Optional[TaskStateChangeCallback] = None,
        on_retry_callback: Optional[TaskStateChangeCallback] = None,
        trigger_rule: str = TriggerRule.ALL_SUCCESS,
        resources: Optional[Dict] = None,
        run_as_user: Optional[str] = None,
        task_concurrency: Optional[int] = None,
        executor_config: Optional[Dict] = None,
        do_xcom_push: bool = True,
        inlets: Optional[Any] = None,
        outlets: Optional[Any] = None,
        task_group: Optional["TaskGroup"] = None,
        **kwargs,
    ):
        from airflow.models.dag import DagContext
        from airflow.utils.task_group import TaskGroupContext
        super().__init__()
        if kwargs: