Expose Ack Timeout length for unit test writing

src/uas/QGCUASFileManager.h

@@ -40,6 +40,10 @@ public:
     bool _sendCmdTestNoAck(void) { return _sendOpcodeOnlyCmd(kCmdTestNoAck, kCOAck); };
     bool _sendCmdReset(void) { return _sendOpcodeOnlyCmd(kCmdReset, kCOAck); };
     
+    /// @brief Timeout in msecs to wait for an Ack time come back. This is public so we can write unit tests which wait long enough
+    /// for the FileManager to timeout.
+    static const int ackTimerTimeoutMsecs = 1000;
+
 signals:
     void statusMessage(const QString& msg);
     void resetStatusMessages();
@@ -142,7 +146,6 @@ protected:
 
     OperationState  _currentOperation;              ///> Current operation of state machine
     QTimer          _ackTimer;                      ///> Used to signal a timeout waiting for an ack
-    static const int    _ackTimerTimeoutMsecs = 1000;   ///> Timeout in msecs for ack timer
     
     UASInterface* _mav;
     quint16 _encdata_seq;