[Python] Refactor CumulativeSumOptions to a separate class for independent deprecation

[bkietz]

Describe the enhancement requested

CumulativeSumOptions are renamed to CumulativeOptions in #36020 after the introduction of cumulative functions other than cumulative_sum which reuse those options. For backward compatibility, an alias was added so that the name CumulativeSumOptions is still usable. However per discussion on that PR the old name should be deprecated, which requires an explicit separate class.

Component(s)

Python

[R-JunmingChen]

Hi @bkietz , I am not sure whether I understand well. It seems that what we need to do is to copy-paste CumulativeOptions and rename it to CumulativeSumOptions?

[R-JunmingChen]

take