Add conf parameter to CLI for airflow dags test

[clellmann]

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This PR adds a feature so that it's possible to pass a DAG run conf via the CLI for debugging DAGs wit "airflow dags test". This closes the gap, that templated operator fields using this DAG run config can also be debugged.

closes: #25671

^ Add meaningful description above

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[boring-cyborg]

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[potiuk]

You likely need to add a case in cli unit tests as well.

[clellmann]

You likely need to add a case in cli unit tests as well.

Thanks for the hint. Will provide this too.

[clellmann]

Hi, I need help regarding the failing git checkout in the pipeline. Can you restart the pipeline or what is the issue?

[potiuk]

restarted. Transient issue. In the futute - you can simply commit --amend and --force push to re-trigger the build

[clellmann]

I need a review here please as everything is green now :)

[boring-cyborg]

Awesome work, congrats on your first merged pull request!