Replace bun workaround with `bun --publish` when it supports trusted publishing

[jsimonrichard]

See oven-sh/bun#15601.

[tunnckoCore]

It's not a workaround 😆 You already have setup-node anyway, so you have zero problem really - just use npm publish, you don't even need bun pm pack && bunx npm publish to begin with.

[jsimonrichard]

I can't use npm publish by itself because it wouldn't resolve workspace dependencies like "@prosemark/core": "workspace:*" correctly... unless I'm missing something.