Core/Logging: Fix crash when trying to log a message while config is being reloaded

Closes #7878

src/server/shared/Logging/Log.cpp

@@ -280,11 +280,14 @@ void Log::vlog(LogFilterType filter, LogLevel level, char const* str, va_list ar
 }
 
 void Log::write(LogMessage* msg)
+{
+    if (worker)
     {
         msg->text.append("\n");
         Logger* logger = GetLoggerByType(msg->type);
         worker->enqueue(new LogOperation(logger, msg));
     }
+}
 
 std::string Log::GetTimestampStr()
 {
@@ -481,6 +484,7 @@ void Log::Close()
 void Log::LoadFromConfig()
 {
     Close();
+    worker = new LogWorker();
     AppenderId = 0;
     m_logsDir = ConfigMgr::GetStringDefault("LogsDir", "");
     if (!m_logsDir.empty())
@@ -488,5 +492,4 @@ void Log::LoadFromConfig()
             m_logsDir.push_back('/');
     ReadAppendersFromConfig();
     ReadLoggersFromConfig();
-    worker = new LogWorker();
 }