Add Alpine package registry (#23714)
This PR adds an Alpine package registry. You can follow [this
tutorial](https://wiki.alpinelinux.org/wiki/Creating_an_Alpine_package)
to build a *.apk package for testing.
This functionality is similar to the Debian registry (#22854) and
therefore shares some methods. I marked this PR as blocked because it
should be merged after #22854.
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Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Giteabot <teabot@gitea.io>
9173e079ae
