Writing MetaSwapModel imported from imod5 model requires to turn off writing validation

[JoerivanEngelen]

Calling:

model = MetaSwapModel.from_imod5_data(...)
model.write(...)

Will throw an error, as all kinds of irrelevant package checks are being done for the options. In its current state, settings files will be copied (just like iMOD5) instead of parsed. We can therefore not check things like whether all the unique values in the landuse grid for GridData are present in the LanduseOptions. So these checks need to be turned off. Right now a user needs to manually turn off validation:

model = MetaSwapModel.from_imod5_data(...)
model.write(..., validate = False)

Modflow6Simulation has a state to turn off certain validation steps, using a ValidationContext.
We can introduce something like in the metaswap module as well.