Ensure to have always only one retry or re-schedule event in place for a CustomResource

[snowdrop-bot]

Currently it can happen that there are multiple events scheduled from reSchedule funtionality. This should not happen, there should be at most one, possibly the earliest keeped in such case. In addition to that we have a automated retry functionality, so we have to think about how this two should work together.

Ideally there is always only 1 of these to is scheduled types scheduled. But also in general there should be at most one timed event coming either of these functionalities.

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operator-framework#601

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$upstream:601$