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
self,
        start_date: Optional[datetime] = None,
        end_date: Optional[datetime] = None,
        ignore_first_depends_on_past: bool = True,
        ignore_ti_state: bool = False,
        mark_success: bool = False,
    ) -> None:
        """Run a set of task instances for a date range."""
        start_date = start_date or self.start_date
        end_date = end_date or self.end_date or timezone.utcnow()
        for execution_date in self.dag.date_range(start_date, end_date=end_date):
            TaskInstance(self, execution_date).run(
                mark_success=mark_success,
                ignore_depends_on_past=(execution_date == start_date and ignore_first_depends_on_past),
                ignore_ti_state=ignore_ti_state,
            )
    def dry_run(self) -> None: