doc: mention BIP86 in doc/bips.md
doc: mention BIP86 in doc/bips.md

Github-Pull: #26443
Rebased-From: 303fb8ff459e67baf97c2ab0b6dd6fa25aff76e3

fujicoin/fujicoin,fujicoin/fujicoin,fujicoin/fujicoin,fujicoin/fujicoin,fujicoin/fujicoin,fujicoin/fujicoin