Added a actual copy of the log context in OStoreDB::SharedQueueLock

The previous case, keeping a reference created a race condition as 2 threads would
use the same logContext.

scheduler/OStoreDB/MemQueues.hpp

@@ -43,7 +43,7 @@ public:
 private:
   std::unique_ptr<objectstore::ScopedExclusiveLock> m_lock;
   std::unique_ptr<objectstore::ArchiveQueue> m_queue;
-  log::LogContext & m_logContext;
+  log::LogContext m_logContext;
   utils::Timer m_timer;
 };