With skip-changelog: true, release-please didn't update the PR body
when new commits landed because the tree SHA was unchanged (no
changelog file to diff). Re-enabling changelogs means each new commit
produces different changelog content, forcing release-please to update
both the branch and PR body.
release-please defaults to walking 500 commits and 400 releases on
every run, making each API call per-commit. With ~20 commits between
releases, this wastes ~2 minutes on unnecessary GitHub API calls.
