message: Fix deadlock in ringbuffer::get_all
diff: @@ -93,7 +93,7 @@ public:
  guard_type guard{mtx_};
  rd_pos_ = (first + n) % Size;
  // Wakeup a waiting producers if the queue became non-full.
  - if (first == next(last))
  + if (first == next(wr_pos_))
  cv_full_.notify_all();
  return i;
  }
  