All logging that happens in BuildNewListFromBlock is currently printed twice.
This is because BuildNewListFromBlock is called while processing the block
and also while calculating the DIP4 MN list commitment.
This commit adds the debugLogs to this method to allow omitting logs while
called from the DIP4 code.
* Properly initialize confirmedHash in CSimplifiedMNListEntry
* Add consensus params for temporary hard-fork on testnet
This hard-fork is required on testnet as we have to fix a few consensus
bugs in DIP3/DIP4. It will also be required to introduce LLMQ commitments
to testnet.
* Add temporary fork-logic for testnet, which sets confirmedHash to null
...before fork activation. Otherwise we'd invalidate all DIP3 blocks on
testnet.
* Bump nTemporaryTestnetForkHeight to 273000
