**Description**

I have noticed that the stable REST API doesn't have the ability to run a task (which is possible from the airflow web interface.
I think it would be nice to have either:
- Run task 
- Run all failing tasks (rerun from point of failure)
this ability for integrations.

**Use case / motivation**

I would like the ability to identify the failing tasks on a specific DAG Run and rerun only them.
I would like to do it remotely (non-interactive) using the REST API.
I could write a script that run only the failing tasks, but I couldn't find a way to "Run" a task, when I have the task instance ID.

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

Not at this stage

**Related Issues**



airflow/models/dag.py
"""
        Set ``is_active=False`` on the DAGs for which the DAG files have been removed.
        Additionally change ``is_active=False`` to ``True`` if the DAG file exists.
        :param alive_dag_filelocs: file paths of alive DAGs
        :param session: ORM Session
        """
        log.debug("Deactivating DAGs (for which DAG files are deleted) from %s table ", cls.__tablename__)
        dag_models = session.query(cls).all()
        try:
            for dag_model in dag_models:
                if dag_model.fileloc is not None:
                    if correct_maybe_zipped(dag_model.fileloc) not in alive_dag_filelocs:
                        dag_model.is_active = False
                    else:
                        
                        
                        if not dag_model.is_active:
                            dag_model.is_active = True
                else:
                    continue
            session.commit()
        except Exception:
            session.rollback()
            raise
    @classmethod
    def dags_needing_dagruns(cls, session: Session):