Add test to confirm Enums serde properly

Author: Dekkonot

tests/roblox/instance/properties.luau

@@ -33,6 +33,16 @@ part.Shape = Enum.PartType.Ball
 
 assert(part.Shape == Enum.PartType.Ball)
 
+-- Enums should roundtrip through serde without problem
+
+local decal = Instance.new("Decal")
+decal.Face = Enum.NormalId.Top
+
+local decal_ser = roblox.serializeModel({ decal })
+local decal_de = roblox.deserializeModel(decal_ser)
+
+assert(decal_de[1].Face == Enum.NormalId.Top)
+
 -- Properties that don't exist for a class should error
 
 local meshPart = Instance.new("MeshPart")