Fix beta releases

[kirrg001]

Hi!

I'd like to suggest to follow the semver specification for prereleases.

2.0.4 is currently published on npm without a beta tag.

The name should be 2.0.4-beta.4.
Following the naming convention, you can remove the beta dist tag on npm, but you can still determine if a release is a prerelease using semver tooling.

Thanks!