**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**


airflow/api_connexion/schemas/dag_run_schema.py
"""Populate execution_date from logical_date for compatibility."""
        data["execution_date"] = data["logical_date"]
        return data
class DAGRunCollection(NamedTuple):