Improve PPND CI testing to confirm that the pausing is occurring at the right times

[juliev0]

Summary

For pipeline update:
Ensure pipeline is paused fully and reaches drainedOnPause and stays that way prior to Pipeline created

For Numaflow Controller update:
Ensure pipeline is paused fully and reaches drainedOnPause and stays that way before Numaflow Controller Pods get deleted, and while there are any of the old Numaflow Controller Pods still running (or possibly prior to new Numaflow Controller Pods created) – speaking of this, have we ever tested this in the case of master/slave Numaflow?

For isbsvc update:
Ensure pipeline is paused fully and reaches drainedOnPause and stays that way from prior to old isbsvc pods being deleted and until all of them are deleted

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Message from the maintainers:

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