Yes I would like to, but I don't have an apple laptop anymore to check if it works so it's not convenient.
If you know how to code or type commands, there are some guidelines here: https://github.com/libretro/ludo/blob/master/.github/workflows/cd.yml#L141-L157
Someone could adapt them to rombundler. But as you can see, apple packaging is quite complex, with code signing and notarization.
EDIT: I have an unfinished pull request here but I don't remember what was wrong with it https://github.com/kivutar/rombundler/pull/34/files