feat: Add Dockerfile with wolfi-base as production image #9029

[amouat]

Draft PR with wolfi based Dockerfile following on from #9029 and #12708.

This is not a distroless Dockerfile. The final image includes a package manager and a shell. If a truly distroless image is wanted, I think @tuananh's proposal is the best solution: https://github.com/tuananh/distroless-argocd. That proposal was rejected (understandably) as it makes large changes to both the build system and base images.

This proposal is something of a half-way house. The production image is moved to wolfi-base, which includes a shell and package manager which allows simple installation of the multiple dependencies required by argocd. The final image is 275MB, which is considerably smaller than the current 417MB image (as reported by docker images).

I have not fully tested this image. It builds, but I wanted to get some feedback before going further. Please let me know what you think and if I should continue down this path.

BTW was there ever an attempt to use alpine? I'm assuming there was an issue there to do with musl vs gllibc?

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Closes [ISSUE 9029] (actually I'm not sure it does, but it's related).

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