DataflowStopJobOperator Operator

[Voldurk]

• _wait_for_states() fix
• _get_current_jobs() and cancel() adjustment to allow stopping multiple jobs by name
• New operator: DataflowStopJobOperator
• Removed batch request from cancel() method as it was not working for gogleapis.dataflow.v1b3.projects.locations.jobs.update

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[potiuk]

Looks good, but could you please make a Howto example (see howto_operator_start_template_job as example on how you can do it - look in the documentation for google providers.

[Voldurk]

@potiuk Updated. Not sure what I can do about that 'unhealthy container' on sql server test.

[potiuk]

Ignore (for now - this is on our flaky-list-to-solve)