ArrayQueryParameter.from_api_repr does not support empty array

[TommyDew42]

The ArrayQueryParameter class must take a StructQueryParameterType if the values is an empty array (docstring):

If the type is 'STRUCT'/'RECORD' and values is empty,
the exact item type cannot be deduced, thus a StructQueryParameterType
instance needs to be passed in.

But in the method _from_api_repr_struct, we simply pass "STRUCT" as the array_type.