Add docs for edge execution_api_server_url

[bdsoha]

The EdgeExecutor defaults to localhost:8080 for core.execution_api_server_url, which does not immediately fail, but causes errors once a job is dequeued.
The newly added documentation guides users on how to properly configure core.execution_api_server_url.

Alternatively, the implementation logic itself could be improved by deriving the value from edge.api_url instead.

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[bdsoha]

@jscheffl If you agree with the alternative implementation I described above, I would be happy to open another PR for it.
What do you think?

[jscheffl]

Thanks for documenting. I never came across this - problably as I always configured correctly.

Other than docs we could also force to set it "better" for example in https://github.com/apache/airflow/blob/main/providers/edge3/src/airflow/providers/edge3/cli/edge_command.py#L81 so that if this is not properly set that we "guess" and assume is is the same base like the edge API URL (which is the same base in 99% of cases...)

[bdsoha]

Other than docs we could also force to set it "better" for example in https://github.com/apache/airflow/blob/main/providers/edge3/src/airflow/providers/edge3/cli/edge_command.py#L81 so that if this is not properly set that we "guess" and assume is is the same base like the edge API URL (which is the same base in 99% of cases...)

That is what I mentioned here, should I open a PR for that?

[jscheffl]

Other than docs we could also force to set it "better" for example in https://github.com/apache/airflow/blob/main/providers/edge3/src/airflow/providers/edge3/cli/edge_command.py#L81 so that if this is not properly set that we "guess" and assume is is the same base like the edge API URL (which is the same base in 99% of cases...)

That is what I mentioned here, should I open a PR for that?

If you like that would be cool!