message: Fix copy/paste typo in starting point definition
  By see AliceO2Group/AliceO2#3583
diff: @@ -272,7 +272,7 @@ int DCAFitterN<N, Args...>::process(const Tr&... args)
  if (dst2 < mMaxDist2ToMergeSeeds) {
  mCrossings.nDCA = 1;
  mCrossings.xDCA[0] = 0.5 * (mCrossings.xDCA[0] + mCrossings.xDCA[1]);
  - mCrossings.xDCA[0] = 0.5 * (mCrossings.xDCA[0] + mCrossings.xDCA[1]);
  + mCrossings.yDCA[0] = 0.5 * (mCrossings.yDCA[0] + mCrossings.yDCA[1]);
  }
  }
  // check all crossings
  