faabc26a61 test: Replace getmempoolentry with testmempoolaccept in MiniWallet (MarcoFalke)
Pull request description:
This is a refactor to not use the return value of `sendrawtransaction` and `getmempoolentry` with the goal that submitting the tx to the mempool will become optional.
ACKs for top commit:
mjdietzx:
ACK faabc26a61
Tree-SHA512: 4260a59e65fed1c807530dad23f1996ba6e881bcce91995f5b498a0be6001f67b3e0251507c8801750fe105410147c68bb2f393ebe678c6a3a4d045e5d72fc19