message: Use debug log level for batch written
diff: @@ -429,7 +429,7 @@ impl Segment<MutLogIndex, MutFileRecords> {
  );
  let (write_success, batch_len, end_file_pos) = self.msg_log.write_batch(batch).await?;
  - info!(
  + debug!(
  write_success,
  batch_len, end_file_pos, next_end_offset, "batch written"
  );
  