message: [Storage] Small improvements to jellyfish merkle restore tests
  Closes:
  Approved by: zamsden
diff: @@ -17,7 +17,7 @@ proptest! {
  fn test_restore_without_interruption(
  btree in btree_map(any::<HashValue>(), any::<AccountStateBlob>(), 1..1000),
  ) {
  - let version = btree.len() as Version - 1;
  + let version = (btree.len() - 1) as Version;
  let expected_root_hash = get_expected_root_hash(&btree);
  // For this test, restore everything without interruption.
  @@ -33,13 +33,13 @@ proptest! {
  #[test]
  fn test_restore_with_interruption(
  - btree1 in btree_map(any::<HashValue>(), any::<AccountStateBlob>(), 1..500),
  - btree2 in btree_map(any::<HashValue>(), any::<AccountStateBlob>(), 1..500),
  + (all, batch1_size) in btree_map(any::<HashValue>(), any::<AccountStateBlob>(), 2..1000)
  + .prop_flat_map(|btree| {
  + let len = btree.len();
  + (Just(btree), 1..len)
  + })
  ) {
  - let batch1_size = btree1.len();
  - let all: BTreeMap<_, _> = btree1.into_iter().chain(btree2.into_iter()).collect();
  - let version = all.len() as Version - 1;
  -
  + let version = (all.len() - 1) as Version;
  let expected_root_hash = get_expected_root_hash(&all);
  let batch1: Vec<_> = all.clone().into_iter().take(batch1_size).collect();
  let db = MockTreeStore::default();
  @@ -81,7 +81,7 @@ fn get_expected_root_hash(btree: &BTreeMap<HashValue, AccountStateBlob>) -> Hash
  .unwrap();
  db.write_tree_update_batch(batch).unwrap();
  }
  - tree.get_root_hash(btree.len() as Version - 1).unwrap()
  + tree.get_root_hash((btree.len() - 1) as Version).unwrap()
  }
  fn assert_success(
  