**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
from airflow.models.dag import DAG
        self.subdag: Optional[DAG] = None
        self._log = logging.getLogger("airflow.task.operators")
        
        self.inlets: List = []
        self.outlets: List = []
        self._inlets: List = []
        self._outlets: List = []
        if inlets:
            self._inlets = (
                inlets
                if isinstance(inlets, list)
                else [
                    inlets,
                ]
            )
        if outlets:
            self._outlets = (
                outlets
                if isinstance(outlets, list)
                else [
                    outlets,
                ]
            )
    def __eq__(self, other):
        if type(self) is type(other) and self.task_id == other.task_id:
            return all(self.__dict__.get(c, None) == other.__dict__.get(c, None) for c in self._comps)
        return False
    def __ne__(self, other):