**Description**

It would be great having a option to abort a DAG Runs through the REST API.

**Use case / motivation**

The proposed input params would be:
 - DAG_ID
 - DAG_RUN_ID

The DAG Run should abort all its tasks running and mark them as "failed".

**Are you willing to submit a PR?**

**Related Issues**


tests/api_connexion/endpoints/test_dag_run_endpoint.py
request_json[logical_date_field_name] = logical_date
        if dag_run_id is not None:
            request_json["dag_run_id"] = dag_run_id
        with mock.patch("airflow.utils.timezone.utcnow", lambda: fixed_now):
            response = self.client.post(
                "api/v1/dags/TEST_DAG_ID/dagRuns",
                json=request_json,
                environ_overrides={"REMOTE_USER": "test"},
            )
        assert response.status_code == 200
        if logical_date is None:
            expected_logical_date = fixed_now.isoformat()
        else:
            expected_logical_date = logical_date
        if dag_run_id is None:
            expected_dag_run_id = f"manual__{expected_logical_date}"
        else:
            expected_dag_run_id = dag_run_id
        assert {
            "conf": {},
            "dag_id": "TEST_DAG_ID",
            "dag_run_id": expected_dag_run_id,
            "end_date": None,
            "execution_date": expected_logical_date,
            "logical_date": expected_logical_date,
            "external_trigger": True,
            "start_date": None,
            "state": "queued",
        } == response.json
    def test_should_response_200_for_matching_execution_date_logical_date(self):