Merge bitcoin/bitcoin#25522: test: Remove -acceptnonstdtxn=1 from feature_rbf.py

fad690b test: Remove -acceptnonstdtxn=1 from feature_rbf.py (MacroFake)
fa5059b test: Make the scriptPubKey of MiniWallet created txs mutable (MacroFake)
fa29245 test: Allow setting sequence per input in MiniWallet create_self_transfer_multi (MacroFake)
fac3800 test: Allow amount_per_output in MiniWallet create_self_transfer_multi (MacroFake)
2222842 test: Allow absolute fee in MiniWallet create_self_transfer (MacroFake)

Pull request description:

  On the main network, nonstandard transactions are hardly relayed, so it seems odd that one of our policy test requires a policy setting opposite of the norm.

  Surely it is also important to test that nonstandard transactions can be replaced. However, rbf code should not care about the standardness at all. Moreover, I think testing nonstandardness rbf is of lower priority than testing the stuff that actually happens in production.

ACKs for top commit:
  theStack:
    re-ACK fad690b
  jamesob:
    ACK fad690b ([`jamesob/ackr/25522.1.MarcoFalke.test_remove_acceptnonstd`](https://github.com/jamesob/bitcoin/tree/ackr/25522.1.MarcoFalke.test_remove_acceptnonstd))

Tree-SHA512: e0a0c808bccdddf738fb6a84e5e5672d7c341bffd941c4f0c232112bfc68265fa81a2e42ddcab107d586358ffdb3dccc46bb5533d46999fd9ab024169dac0f78

Author: MacroFake