Releasing Livebook

If applicable, release Kino first and update built-in notebooks to reference the new version.
Switch to (or create) vx.y branch.
If applicable cherry-pick the relevant commits from main onto the vx.y branch.
Update version in mix.exs, rel/app_next/src-tauri/Cargo.toml, rel/app_next/src-tauri/Cargo.lock and finish changelog.
Run mix hex.build as a sanity check.
git tag vx.y.z, git push --tags
1. Wait for CI to finish (Docker and Desktop)
Run mix hex.publish.
Publish GH release with copied changelog notes.
If you created a branch in step 2., update main changelog to point to the branch and bump version in mix.exs (with -dev suffix).