**Apache Airflow version**:
v2.0.0

**What happened**:

Custom operators inheriting from DummyOperator are go in to a scheduled state, where as DummyOperator itself is set straight to success.

**What you expected to happen**:

All operators should be successfully executed.

**How to reproduce it**:

```py
from datetime import datetime
from airflow import DAG
from airflow.operators.dummy_operator import DummyOperator

class MyJob(DummyOperator):
    template_fields_renderers = {
        "body": "json"
    }
    template_fields = ("body",)

    def __init__(self, body, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.body = body

with DAG(
    dag_id="test",
    schedule_interval=None,
    start_date=datetime(2020, 8, 13),
) as dag:
    MyJob(task_id="aaaa", body={"aaa": "bbb"})

```

**Anything else we need to know**:
This is a known problem that we will fix, see: https://github.com/apache/airflow/pull/10956#discussion_r502492775
airflow/models/baseoperator.py
return not self == other
    def __hash__(self):
        hash_components = [type(self)]
        for component in self._comps:
            val = getattr(self, component, None)
            try:
                hash(val)
                hash_components.append(val)
            except TypeError:
                hash_components.append(repr(val))
        return hash(tuple(hash_components))
    
    def __or__(self, other):
        """
        Called for [This Operator] | [Operator], The inlets of other
        will be set to pickup the outlets from this operator. Other will
        be set as a downstream task of this operator.
        """
        if isinstance(other, BaseOperator):
            if not self._outlets and not self.supports_lineage:
                raise ValueError("No outlets defined for this operator")
            other.add_inlets([self.task_id])
            self.set_downstream(other)
        else:
            raise TypeError(f"Right hand side ({other}) is not an Operator")
        return self
    
    def __gt__(self, other):