Support HierarchyID as data type in SQL Warehouse

[Jugi]

The hierachyID is a pretty useful datatype to store huge hierarchies very performant. It would be very nice if this is supported by the Warehouse

https://learn.microsoft.com/en-us/sql/t-sql/data-types/hierarchyid-data-type-method-reference