message: Use the more concise `prepare_bytes()`
diff: @@ -106,9 +106,7 @@ mod test {
  fn prepare_bytes(length: usize) -> Vec<u8> {
  let mut rng = rand::thread_rng();
  - let mut v = Vec::with_capacity(length);
  - (0..length).into_iter().for_each(|_| v.push(rng.gen()));
  - v
  + (0..length).into_iter().map(|_| rng.gen()).collect()
  }
  impl ChunkWithProof {
  