More concise error message in the api-server log when execution_api_server_url isn't correct

[radumas]

Description

When the execution_api_server_url config variable isn't correct, the consequences are:

• Tasks don't run successfully
• task state mismatch under Events tab in the UI base_url gives state mismatch and task fail error. #50191

These don't explicitly identify the root cause.

Use case/motivation

It should be easier to identify when something core in the configuration is misconfigured such that the different components of Airflow can't communicate with each other. This could be evident from:

• a configuration checker (like airflow config check)
• On the homepage of the UI? More details when one of the components has a big red X
• In the api-server log (or the scheduler log?)

Related issues

The symptoms of misconfiguration were first identified here #50191

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