message: Fix StreamReader reading step by step. It only read one block if index and never updated.
diff: @@ -578,7 +578,7 @@ size_t BP4Reader::UpdateBuffer(const TimePoint &timeoutInstant,
  m_MDFileAbsolutePos = m_MDFileAlreadyReadSize;
  m_MDFileAlreadyReadSize = expectedMinFileSize;
  - m_MDIndexFileAlreadyReadSize = idxFileSize;
  + m_MDIndexFileAlreadyReadSize += newIdxSize;
  sizes[0] = newIdxSize;
  sizes[1] = m_MDFileAlreadyReadSize;
  