[actionpins] Make per-repo pin sorting mutation explicit in buildByRepoIndex#41427

pelikhan with Copilot wants to merge 2 commits into

maingithub/gh-aw:mainfrom

copilot/fp-enhancer-improve-pkg-actionpinsgithub/gh-aw:copilot/fp-enhancer-improve-pkg-actionpinsCopy head branch name to clipboard