### Description


We need to access the time at which a given DAG was parsed last.

Airflow Version : 2.2.2 and above.

### Use case/motivation

End users want to run a given DAG post applying the changes they have done on them. This would mean that the DAG should be parsed post the edits done to it. Right now the last parsed time is available by accessing the airflow database only. Querying the database directly is not the best solution to the problem. Ideally airflow should be exposing APIs that end users can consume that can help provide the last parsed time for a given DAG.

### Related issues

Not Aware.

### 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)

from airflow.models.dag import DAG
from airflow.models.serialized_dag import SerializedDagModel
from airflow.timetables.base import DataInterval
from airflow.utils import cli as cli_utils, timezone
from airflow.utils.cli import get_dag, get_dags, process_subdir, sigint_handler, suppress_logs_and_warning
from airflow.utils.dot_renderer import render_dag, render_dag_dependencies
from airflow.utils.session import NEW_SESSION, create_session, provide_session
from airflow.utils.state import DagRunState
log = logging.getLogger(__name__)
def _run_dag_backfill(dags: list[DAG], args) -> None:
    
    args.end_date = args.end_date or args.start_date
    args.start_date = args.start_date or args.end_date
    run_conf = None
    if args.conf:
        run_conf = json.loads(args.conf)
    for dag in dags:
        if args.task_regex:
            dag = dag.partial_subset(
                task_ids_or_regex=args.task_regex, include_upstream=not args.ignore_dependencies
            )
            if not dag.task_dict:
                raise AirflowException(
                    f"There are no tasks that match '{args.task_regex}' regex. Nothing to run, exiting..."
                )
        if args.dry_run:
            print(f"Dry run of DAG {dag.dag_id} on {args.start_date}")
            dr = DagRun(dag.dag_id, execution_date=args.start_date)
            for task in dag.tasks:
                print(f"Task {task.task_id} located in DAG {dag.dag_id}")