[FEATURE]: Optionally add sklearn's TimeSeriesSplit

[kspieks]

Our current time-based splitter only returns one split of the data. If users want multiple time-based splits, they would need to make multiple calls. We could definitely write a short function that wrap ours, but I'll just also share this as another option. It would require the data to already be sorted by time
https://scikit-learn.org/stable/modules/generated/sklearn.model_selection.TimeSeriesSplit.html

[JacksonBurns]

@kspieks this would be a cool one to have - this would ignore the requested split sizes, right?

[kspieks]

Yes this specific splitter would ignore the split size arguments. Not sure if that would be confusing to the user but it would be consistent with the function call for TimeSeriesSplit()

[JacksonBurns]

Following up on this after some time - now that astartes is used in a few different places, we see that it is easier to require the end users to make repeat calls rather than for us to implement it here. Going to go ahead and close this, but leave it as not completed since this may change in the future.