refactor: use variants in zone instead of only game

test/ObjCompilingTests/Image/ImageIwdPostProcessorTest.cpp

@@ -19,7 +19,7 @@ namespace
     {
     public:
         TestContext()
-            : m_zone("test", 0, GameId::T6, GamePlatform::PC),
+            : m_zone("test", 0, GameVariantId::T6_PC),
               m_zone_definition(),
               m_zone_definition_context(m_zone_definition),
               m_zone_states(m_zone),