Fix panic on receiving `channel_ready` after 1st commitment update#2071

TheBlueMatt merged 1 commit intolightningdevkit:mainlightningdevkit/rust-lightning:mainfrom

TheBlueMatt:2023-01-fix-fast-extra-ready-panicTheBlueMatt/rust-lightning:2023-01-fix-fast-extra-ready-panicCopy head branch name to clipboard