Update api::Sort to use TypeNode instead of Type (#5363)

Update api::Sort to use TypeNode instead of Type (#5363)

This is work towards removing the old API.

This makes TypeNode the backend for Sort instead of Type.

It also updates a unit test for methods isUninterpretedSortParameterized and getUninterpretedSortParamSorts whose implementation was previously buggy due to the implementation of Type-level SortType.