Port LocalTaskJob tests to Task SDK

[kaxil]

To get more confidence in the new Supervisor process in the Task SDK, we should investigate and port over tests from LocalTaskJob and some from models.TI to Task SDK's superisor's test

[kaxil]

WIP: https://github.com/apache/airflow/compare/main...astronomer:airflow:ltj-tests?expand=1

[kaxil]

#44405 & #44405 got merged

PRs:

• AIP-72: Add escalation path for killing process in Supervisor #44465

[kaxil]

Next Up:

• Port overtime to handle OL -- local task job: add overtime mechanism, to not kill task prematurely when auxiliary processes are running #39890 -- to Supervisor