test: suppress a wrong warning with toolset v141

test/entt/entity/registry.cpp

@@ -1762,7 +1762,7 @@ TEST(Registry, GetOrEmplace) {
     const auto entity = registry.create();
     const auto value = registry.get_or_emplace<int>(entity, 3);
     // get_or_emplace must work for empty types
-    registry.get_or_emplace<empty_type>(entity);
+    static_cast<void>(registry.get_or_emplace<empty_type>(entity));
 
     ASSERT_TRUE((registry.all_of<int, empty_type>(entity)));
     ASSERT_EQ(registry.get<int>(entity), value);