merge fix

src/minefield.cpp

@@ -57,14 +57,13 @@ void MineField::initBombs(int x, int y) {
   startTimer();
 
   //init the timer to zero and start the timer thread
-  //  m_time = 0;
-  //timerThread = std::thread(&MineField::timerTick, this);
   //timerThread.detach(); //not sure if this is okay (better to call join() when I set the condition to stop the thread)
 }
 
 bool MineField::openCell(int x, int y) {
   if(isBomb(x, y)) {
     m_exploded = true;
+    timerThread.join();
     gameOverSignal.emit();
     stopTimer();
     return false;