Starting to decouple tests from a specific CashAddr prefix, hardcode the _scriptPubKey_ of the miner fund instead of bitcoincash:pqnqv9lt7e5vjyp0w88zf2af0l92l8rxdgnlxww9j9
also test the miner fund against the address reported by the getblocktemplate RPC instead of hardcoding it in the test. that required spinning an additional node for the test, otherwise gbt fails with "Bitcoin is not connected!"