@hookimpl on_dag_run_running, on_dag_run_success, on_dag_run_failed do not find Connections and Variables

### Apache Airflow version Other Airflow 2 version (please specify below) ### If "Other Airflow 2 version" selected, which one? 2.8.1 ### What happened? I wrote a listener plugin and added it to the plugins directory. The listener includes the methods: - on_task_instance_running - on_task_instance_success - on_task_instance_failed - on_dag_run_running - on_dag_run_success - on_dag_run_failed. When trying to extract values from Variables and Connections in the on_dag_run_running, on_dag_run_success, on_dag_run_failed methods, an error occurs already when running dag run: ``` Traceback (most recent call last): File "/home/airflow/.local/lib/python3.9/site-packages/airflow/cli/commands/scheduler_command.py", line 52, in _run_scheduler_job run_job(job=job_runner.job, execute_callable=job_runner._execute) File "/home/airflow/.local/lib/python3.9/site-packages/airflow/utils/session.py", line 79, in wrapper return func(*args, session=session, **kwargs) File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/job.py", line 393, in run_job return execute_job(job, execute_callable=execute_callable) File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/job.py", line 422, in execute_job ret = execute_callable() File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job_runner.py", line 855, in _execute self._run_scheduler_loop() File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job_runner.py", line 987, in _run_scheduler_loop num_queued_tis = self._do_scheduling(session) File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job_runner.py", line 1063, in _do_scheduling self._start_queued_dagruns(session) File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job_runner.py", line 1404, in _start_queued_dagruns dag_run.notify_dagrun_state_changed() File "/home/airflow/.local/lib/python3.9/site-packages/airflow…