Fix Finalization when other finalizers are in place

[similark]

The webhook's isRemovingFinalizer func should check whether the change is less finalizers, obviously, and not specifically check whether the old Scaledobject has exactly 1 finalizer AND the new Scaled object has exactly 0.
This is to fix a use case in which ArgoCD performs cascading deletion which translates to a foregroundDeletion finalizer being added to the object, causing the current webhook implementation enter a loop of update-validate ("if not isRemovingFinalizer then update") instead of proceeding with deletion.

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[JorTurFer]

Nice catch!
Thanks for the fix :)

[JorTurFer]

/run-e2e internal
Update: You can check the progress here

[JorTurFer]

/run-e2e internal
Update: You can check the progress here

[similark]

Not sure the failing check is relevant to my change 🤔

[zroubalik]

/run-e2e pause_scaledjob_test
Update: You can check the progress here