cache: iterator_concept

src/entt/resource/cache.hpp

@@ -37,6 +37,7 @@ public:
     using reference = value_type;
     using difference_type = std::ptrdiff_t;
     using iterator_category = std::input_iterator_tag;
+    using iterator_concept = std::random_access_iterator_tag;
 
     constexpr resource_cache_iterator() noexcept = default;