Remove deprecations for v0.4.0

[jobrachem]

• [ ] liesel.model.legacy.Param
• [ ] liesel.model.legacy.Obs
• [ ] liesel.goose.engine.SamplingResult
• [ ] liesel.goose.summary_m.Summary.from_result
• [ ] liesel.goose.summary_m.Summary.from_results
• [ ] liesel.model.goose.GooseModel -> (renamed/moved) liesel.goose.interface.LieselInterface
• [ ] liesel.goose.models.DictModel -> (renamed/moved) liesel.goose.interface.DictInterface
• [ ] liesel.goose.models.DataClassModel -> (renamed/moved) liesel.goose.interface.DataclassInterface