Make sure PPND will be okay with the latency of Pipeline/ISBService informers

[juliev0]

this is based on this comment

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[juliev0]

I came up with at least one case where it wouldn't be good:
once PipelineRollout Reconciler has update the Pipeline spec, it will check to see if the Pipeline is still reconciling in order to know whether it can resume the Pipeline or not. If we get an old copy of the Pipeline spec whose generation still shows the previous generation, then its observedGeneration would in fact match the generation, and then we'd resume the Pipeline prematurely.

For this reason, I think if we currently have the PPND InProgressStrategy (saved in memory), then we should reach out to the K8S API to get the latest spec rather than just using the one from the Informer.