Resolve test pool unit test warnings

[idantepper]

related: #38642

I removed the initialization of TaskInstance from using execution_date to using run_id
before changing when running the tests the following warn was given
https://github.com/apache/airflow/blob/main/airflow/models/taskinstance.py

            warnings.warn(
                "Passing an execution_date to `TaskInstance()` is deprecated in favour of passing a run_id",
                RemovedInAirflow3Warning,
                # Stack level is 4 because SQLA adds some wrappers around the constructor
                stacklevel=4,
            )