[Optimizers] Make all available optimizers through a "string" be instatiable without kwargs

[eddiebergman]

WIP Issue... Just submitting it to get a number to put in code for now

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The optimizers support a lot of configuration but we make sure to have sensible defaults. However some optimizers do not run without extra keyword arguments specified

• All optimizers should be able to be instantiated with OptimizerCls(pipeline_space=space)
  • "assisted_regularized_evolution": assert not assisted or (assisted and assisted_zero_cost_proxy is not None) - It won't run with defaults, it has assisted as True and assisted_zero_cost_proxy = None, needing to be specified.
  • "successive_halving_prior" requires a budget to be specified while "successive_halving"does not. I'm not sure which one is incorrect. It seems likeSuccessiveHalvingwill just passbudget=None` to base Optimizer and move on with its day... not sure what the behaviour is in this case.