fix SMT tests so build with SMTs enabled does not fail (and work)

Fixed compilation problems in SMT tests, the same way as other tests were changed before.

There is a problem with get_transaction_signature_validation_rules_at_time. Obviously the main problem is that it is detached from actual application of hardforks, however until we need to change some rules for future hardfork (when that scheme will fail) it works for mirrornet and mainnet. In testnet however, especially in unit tests, the problem is that given time has no connection to when hardforks are applied. Since in most cases hardforks are triggered right after genesis, it turned out hardcoding post_hf_0_20_rules is enough for a workaround. But it is yet another difference between testnet and other builds.