Publish package to npm and ghcr

[Vad1mo]

Since we received these backstage plugins, there have been already quite a few contributions from the community.

We would like to publish NPM Packages to npmjs and to ghcr.

Create GitHub Action
Create a deployment strategy to automatically publish packages for new version
Publish packages to npmjs
Publish packages to ghcr
There as quite some GH Actions on the marketplace, we need to choose one.

https://github.com/marketplace?category=&query=npm+sort%3Atop-30-desc+updated%3A%3E2023-11-11&type=actions&verification=

https://github.com/marketplace/actions/npm-publish