Allow Newspack Plugin to self-update from Github via core plugin headers #4234
Description
Is your feature request related to a problem? Please describe.
While the Newspack Plugin enables installing and updating its sub-plugins from GitHub, it doesn't currently seem to support updating itself. This can cause issues if there is an API change at some point with the sub-plugin updating but the main plugin not, potentially resulting in fatal errors.
Describe the solution you'd like
It'd be ideal if the Newspack plugin could implement the Update URI functionality from WordPress 5.8, allowing it to query this repository for updated releases and offer them as updates.
Describe alternatives you've considered
Alternately, if the main Newspack plugin were shipped to WordPress.org and made available there, however that would have broader impacts on the ecosystem about how it installs its sub-modules from GitHub violating repo guidelines. Also, it could be set up to seek the update details from newspack.com rather than github.com to provide more insight into usage (ideally with a disclaimer and user consent).
Additional context
This came about when I was looking at a test install I had locally, and noticed that not only was a sub-module (Newsletters in this case) offering to update, I also noticed that the version on the Newspack Plugin itself was far out of date. I am concerned about this resulting in eventual incompatabilities and support issues down the road.