Refactor dataproc system tests

[VladaZakharova]

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[potiuk]

Some static checks. As usuall - I recommend to have pre-commit installed, it fixes all those problems automatically :)

[shahar1]

LGTM overall - static checks should be fixed as Jarek mentioned.
Also, I assume that there was a reason for changing the regions in the system tests - is there any policy for that? (I think that it should be mentioned somwhere)

[VladaZakharova]

@potiuk @shahar1 hi! thank you for checking this one. Changes in regions and locations were made only to fix the problem in our Composer CI: with previous setup there was a big load on one specific region that was used in all of them. This PR fixes this, but the rest in the test remains the same.
I will try to fix static checks, but there is one that I don't know how to :)
In dataproc_batch we have task that runs cancel_operation() method to cancel any long-running operation. In this case it should be run in parallel with the task that performs that long-running operation (create_batch_4) and since the operation was cancelled, the task itself is failed. Watcher sees the failed task and marks the whole DAG as failed. I was trying to exclude this create_task from the list for watcher, but static check is failing because of that. Do you have some ideas maybe how I can fix it?

[potiuk]

I will try to fix static checks, but there is one that I don't know how to :)

In this pre-commit:

airflow/scripts/ci/pre_commit/check_system_tests.py

Line 55 in 965d752

index = content.find(WATCHER_APPEND_INSTRUCTION)

Just have a `>> watcher()`` check instead of the full append instructions