Unify doc-strings (remove type/rtype)

As this information is already provided in type hints and we don't need to maintain it in two places.

src/ifcopenshell-python/ifcopenshell/api/style/unassign_material_style.py

@@ -33,16 +33,12 @@ def unassign_material_style(
     This does the inverse of assign_material_style.
 
     :param material: The IfcMaterial which you want to unassign the style from.
-    :type material: ifcopenshell.entity_instance
     :param style: The IfcPresentationStyle (typically IfcSurfaceStyle) that
         you want to unassign from material. This will then be applied to all
         objects that have that material.
-    :type style: ifcopenshell.entity_instance
     :param context: The IfcGeometricRepresentationSubContext at which this
         style should be unassigned. Typically this is the Model BODY context.
-    :type context: ifcopenshell.entity_instance
     :return: None
-    :rtype: None
 
     Example: