Bump cargo-dist to 0.30.4 (#18158)
This PR was generated by:
1. bumping the version number in `dist-workspace.toml`
2. removing `dist.allow-dirty` in `dist-workspace.toml`
3. running `cargo dist generate`
4. adding back the `custom-publish-pypi` dependency for
`custom-publish-crates`
5. reverting step 2
