Issue title: feature request: release package to GitHub
 Issue body: The result of `npm pack` should be uploaded to GitHub by default when a GitHub release is made.
 Comments: 
 Comment 0: Why do you think this should be the default? I think there can be many files output by `npm pack` that should generally not be part of a GitHub release.
 Comment 1: 1. I am speaking specifically of JS projects that are also being published to a centralized package manager like npm.
2.  GitHub releases contain a zip of all source files. So `npm pack` will inherently contain less files.
3. One expects a release to be consumable in a project. This is the main point. Otherwise a GitHub release is just a fancy changelog entry.
4. Users would not need to rely on npm as the only source for said release.
 Comment 2: Do you know about https://github.com/features/package-registry? Sounds like this is basically what you're after.
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