Add npm publish script

We need to be able to publish npm packages to our internal package registry after the package version gets bumped. Since the commit from the release script skips pipelines, we need to do it in the same pipeline, and it makes sense to run it in this image.

We could run the commands manually for the ui-components library, as it's currently the only one we're publishing internally, but the script can be made completely generic and would prevent mistakes happening if we need to do this again.