### Description

Allow users to re-use recent DagRun configurations upon running a DAG.
This can be achieved by adding a dropdown that contains some information about recent configurations. When user selects an item, the relevant JSON configuration can be pasted to the "Configuration JSON" textbox.
<img width="692" alt="Screen Shot 2022-11-16 at 16 22 30" src="https://user-images.githubusercontent.com/39705397/202209536-c709ec75-c768-48ab-97d4-82b02af60569.png">
<img width="627" alt="Screen Shot 2022-11-16 at 16 22 38" src="https://user-images.githubusercontent.com/39705397/202209553-08828521-dba2-4e83-8e2a-6dec850086de.png">
<img width="612" alt="Screen Shot 2022-11-16 at 16 38 40" src="https://user-images.githubusercontent.com/39705397/202209755-0946521a-e1a5-44cb-ae74-d43ca3735f31.png">


### Use case/motivation

Commonly, DAGs are triggered using repetitive configurations. Sometimes the same configuration is used for triggering a DAG, and sometimes, the configuration differs by just a few parameters. 

This interaction forces a user to store the templates he uses somewhere on his machine or to start searching for the configuration he needs in `dagrun/list/`, which does take extra time.

It will be handy to offer a user an option to select one of the recent configurations upon running a DAG.

### Related issues

_No response_

### Are you willing to submit a PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

"""Import variables"""
        try:
            variable_dict = json.loads(request.files["file"].read())
        except Exception:
            self.update_redirect()
            flash("Missing file or syntax error.", "error")
            return redirect(self.get_redirect())
        else:
            suc_count = fail_count = 0
            for k, v in variable_dict.items():
                try:
                    models.Variable.set(k, v, serialize_json=not isinstance(v, str))
                except Exception as e:
                    logging.info("Variable import failed: %s", repr(e))
                    fail_count += 1
                else:
                    suc_count += 1
            flash(f"{suc_count} variable(s) successfully updated.")
            if fail_count:
                flash(f"{fail_count} variable(s) failed to be updated.", "error")
            self.update_redirect()
            return redirect(self.get_redirect())
class JobModelView(AirflowModelView):
    """View to show records from Job table"""