message: NO-TICKET: Fix the flaky test.
  It was possible that the test generated two switch blocks in the same era, in which case it will fail when updating the index in the storage.
diff: @@ -449,9 +449,24 @@ fn can_retrieve_block_by_height() {
  let mut storage = storage_fixture(&harness);
  // Create a random block, load and store it.
  - let block_33 = random_block_at_height(&mut harness.rng, 33);
  - let block_14 = random_block_at_height(&mut harness.rng, 14);
  - let block_99 = random_block_at_height(&mut harness.rng, 99);
  + let block_33 = Box::new(Block::random_with_specifics(
  + &mut harness.rng,
  + EraId::new(1),
  + 33,
  + true,
  + ));
  + let block_14 = Box::new(Block::random_with_specifics(
  + &mut harness.rng,
  + EraId::new(1),
  + 14,
  + false,
  + ));
  + let block_99 = Box::new(Block::random_with_specifics(
  + &mut harness.rng,
  + EraId::new(2),
  + 99,
  + true,
  + ));
  // Both block at ID and highest block should return `None` initially.
  assert!(get_block_at_height(&mut harness, &mut storage, 0).is_none());
  