Add source after installing apk packages to avoid breaking docker cache

[skwp]

Currently, changing the source code causes the docker layer cache to break the caching of package installation (make, git, etc). This makes rebuilds of the container due to source code changes unnecessarily expensive.

If we execute the source COPY command as an individual command, after the installation of the OS packages, then rebuilds of the container will be much quicker.

Pull Request Checklist

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[skwp]

the only change in this PR is moving the COPY line after the RUN apk add

[guggero]

LGTM, thanks!

[halseth]

LGTM 🗞