Point users to a TaskInstance's Event Log if tasks are missing

[RNHTTR]

Description

Task logs can be missing for a wide variety of reasons. Two of the most common ones are:

• The task was stuck in queued and failed by task_queued_timeout
• The task became a zombie

In these scenarios, it'd be helpful to populate the TaskInstance's logs with a message pointing users to the TaskInstance's Event Log.

Related issues

• Improve Airflow's debugging story #40975
• Task fails and cannot read logs. Invalid URL 'http://:8793/log/...': No host supplied #42136

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[potiuk]

I moved it to "Debugging Improvements" project @RNHTTR -> the result of the debugging survey prepared by @omkar-foss and team has been turned into a number of action points discussed there and I strongly feel (if you agree with me) that this one falls into the same "bucket". So far we are only discussing what could be done there and there are few small things implemented, but possibly that one should go there as well.