test: try to make all compilers happy again

test/entt/entity/entity.cpp

@@ -58,7 +58,7 @@ TYPED_TEST(Entity, Traits) {
     ASSERT_EQ(traits_type::next(entt::tombstone), traits_type::construct(entt::null, {}));
     ASSERT_EQ(traits_type::next(entt::null), traits_type::construct(entt::null, {}));
 
-    if constexpr(traits_type::to_integral(tombstone) != ~traits_type::entity_type{}) {
+    if constexpr(traits_type::to_integral(tombstone) != ~typename traits_type::entity_type{}) {
         // test reserved bits, if any
         constexpr entity_type reserved{traits_type::to_integral(entity) | (traits_type::to_integral(tombstone) + 1u)};
 

test/entt/entity/sparse_set.cpp

@@ -766,7 +766,7 @@ TYPED_TEST(SparseSet, Contains) {
         ASSERT_FALSE(set.contains(entity));
         ASSERT_FALSE(set.contains(other));
 
-        if constexpr(traits_type::to_integral(entt::tombstone) != ~traits_type::entity_type{}) {
+        if constexpr(traits_type::to_integral(entt::tombstone) != ~typename traits_type::entity_type{}) {
             // test reserved bits, if any
             constexpr entity_type reserved{traits_type::to_integral(entity) | (traits_type::to_integral(entt::tombstone) + 1u)};