Sometimes it can be hard to persist all changes at ones, the process
can take almost all RAM and a lot of time. Here's the example of reset
for mainnet from 2.4M to 1:
```
anna@kiwi:~/Documents/GitProjects/nspcc-dev/neo-go$ ./bin/neo-go db reset -m --height 1
2022-11-20T17:16:48.236+0300 INFO MaxBlockSize is not set or wrong, setting default value {"MaxBlockSize": 262144}
2022-11-20T17:16:48.236+0300 INFO MaxBlockSystemFee is not set or wrong, setting default value {"MaxBlockSystemFee": 900000000000}
2022-11-20T17:16:48.237+0300 INFO MaxTransactionsPerBlock is not set or wrong, using default value {"MaxTransactionsPerBlock": 512}
2022-11-20T17:16:48.237+0300 INFO MaxValidUntilBlockIncrement is not set or wrong, using default value {"MaxValidUntilBlockIncrement": 5760}
2022-11-20T17:16:48.240+0300 INFO restoring blockchain {"version": "0.2.6"}
2022-11-20T17:16:48.297+0300 INFO initialize state reset {"target height": 1}
2022-11-20T17:16:48.300+0300 INFO trying to reset blocks, transactions and AERs
2022-11-20T17:19:29.313+0300 INFO blocks, transactions ans AERs are reset {"took": "2m41.015126493s", "keys": 3958420}
...
```
To avoid OOM killer, split blocks reset into multiple stages. It increases
operation time due to intermediate DB persists, but makes things cleaner, the
result for almost the same DB height with the new approach:
```
anna@kiwi:~/Documents/GitProjects/nspcc-dev/neo-go$ ./bin/neo-go db reset -m --height 1
2022-11-20T17:39:42.023+0300 INFO MaxBlockSize is not set or wrong, setting default value {"MaxBlockSize": 262144}
2022-11-20T17:39:42.023+0300 INFO MaxBlockSystemFee is not set or wrong, setting default value {"MaxBlockSystemFee": 900000000000}
2022-11-20T17:39:42.023+0300 INFO MaxTransactionsPerBlock is not set or wrong, using default value {"MaxTransactionsPerBlock": 512}
2022-11-20T17:39:42.023+0300 INFO MaxValidUntilBlockIncrement is not set or wrong, using default value {"MaxValidUntilBlockIncrement": 5760}
2022-11-20T17:39:42.026+0300 INFO restoring blockchain {"version": "0.2.6"}
2022-11-20T17:39:42.071+0300 INFO initialize state reset {"target height": 1}
2022-11-20T17:39:42.073+0300 INFO trying to reset blocks, transactions and AERs
2022-11-20T17:40:11.735+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 1, "took": "29.66363737s", "keys": 210973}
2022-11-20T17:40:33.574+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 2, "took": "21.839208683s", "keys": 241203}
2022-11-20T17:41:29.325+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 3, "took": "55.750698386s", "keys": 250593}
2022-11-20T17:42:12.532+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 4, "took": "43.205892757s", "keys": 321896}
2022-11-20T17:43:07.978+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 5, "took": "55.445398156s", "keys": 334822}
2022-11-20T17:43:35.603+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 6, "took": "27.625292032s", "keys": 317131}
2022-11-20T17:43:51.747+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 7, "took": "16.144359017s", "keys": 355832}
2022-11-20T17:44:05.176+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 8, "took": "13.428733899s", "keys": 357690}
2022-11-20T17:44:32.895+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 9, "took": "27.718548783s", "keys": 393356}
2022-11-20T17:44:51.814+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 10, "took": "18.917954658s", "keys": 366492}
2022-11-20T17:45:07.208+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 11, "took": "15.392642196s", "keys": 326030}
2022-11-20T17:45:18.776+0300 INFO intermediate batch of removed blocks, transactions and AERs is persisted {"batches persisted": 12, "took": "11.568255716s", "keys": 299884}
2022-11-20T17:45:25.862+0300 INFO last batch of removed blocks, transactions and AERs is persisted {"batches persisted": 13, "took": "7.086079594s", "keys": 190399}
2022-11-20T17:45:25.862+0300 INFO blocks, transactions ans AERs are reset {"took": "5m43.791214084s", "overall persisted keys": 3966301}
...
```
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