Improve argument names to follow the auto-sklearn 2.0 paper

[mfeurer]

The current API, the Auto-sklearn 2.0 paper nomenclature and scikit-learn nomencature are different:

current API	Auto-sklearn 2.0 terminology	sklearn	should be named
resampling_strategy	model selection strategy	cv	model_selection_strategy or cv
resampling_strategy_arguments	-	-	model_selection_strategy_kwargs or cv_kwargs

In addition, we need to add an argument budget_selection_strategy that replaces standard holdout by successive halving.