Fix bug in Dataflow hook when no jobs are returned

[keze]

There was a bug which assumed that there will be always some job when fetching jobs from DataFlow which caused KeyError in DataFlow hook.

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[boring-cyborg]

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[kosteev]

is this what is needed here? I believe this block of code is formatted fine

[keze]

If I remove turning off and on formatter it will be too long one liner

[uranusjr]

It's not too long if the formatter says it's OK 🙂

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[boring-cyborg]

Awesome work, congrats on your first merged pull request!