fix crash on green user restoration

src/managers/BetterInfoCache.cpp

@@ -150,7 +150,7 @@ std::string BetterInfoCache::getUserName(int userID, bool download) {
         //if gdhistory was faster, this could be sync and the feature would be more efficient, sadly gdhistory is not faster
         if(download && m_attemptedUsernames.find(userID) == m_attemptedUsernames.end()) {
             web::AsyncWebRequest().fetch(fmt::format("https://history.geometrydash.eu/api/v1/user/{}/brief/", userID)).json().then([userID](const matjson::Value& data){
-                log::info("Restored green username for {}: {}", userID, data.as_string());
+                log::info("Restored green username for {}: {}", userID, data.dump(matjson::NO_INDENTATION));
                 std::string username;
 
                 if(data["non_player_username"].is_string()) username = data["non_player_username"].as_string();