dense_map: suppress warnings due to possible narrowing conversions

src/entt/container/dense_map.hpp

@@ -273,7 +273,7 @@ class dense_map {
 
     template<typename Other>
     [[nodiscard]] std::size_t key_to_bucket(const Other &key) const noexcept {
-        return fast_mod(sparse.second()(key), bucket_count());
+        return fast_mod(static_cast<size_type>(sparse.second()(key)), bucket_count());
     }
 
     template<typename Other>