**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
do_it = True
        if count == 0:
            return 0
        if confirm_prompt:
            ti_list = "\n".join([str(t) for t in tis])
            question = (
                "You are about to delete these {count} tasks:\n{ti_list}\n\nAre you sure? (yes/no): "
            ).format(count=count, ti_list=ti_list)
            do_it = utils.helpers.ask_yesno(question)
        if do_it:
            clear_task_instances(
                tis,
                session,
                dag=self,
                activate_dag_runs=False,  
            )
            self.set_dag_runs_state(
                session=session,
                start_date=start_date,
                end_date=end_date,
                state=dag_run_state,
                dag_ids=dag_ids,
            )
        else:
            count = 0
            print("Cancelled, nothing was cleared.")
        session.commit()
        return count
    @classmethod
    def clear_dags(