Reduce docker image size

[edeNFed]

This PR changes the base image to be gcr.io/distroless/base
Image size before the change: 172MB
Image size after the change: 23.8MB

[MikeGoldsmith]

We have set dependency requirements for the runtime image, maybe looking to build our own using the ChainGuard image as a guide would be better? Then we'd at least be in control of dependency updates and publish schedules & versioning.

[edeNFed]

@pellared @MrAlias
This is ready for another review.
Changed from the Chainguard image to Google distroless and used the sha256 digest as version

[dineshg13]

LTGM

[MrAlias]

For reference, I think this is the repository the images are generated from: https://github.com/GoogleContainerTools/distroless

[MrAlias]

It looks like there are support timelines: https://github.com/GoogleContainerTools/distroless/blob/main/SUPPORT_POLICY.md

[MrAlias]

Docs:

Image Contents

This image contains a minimal Linux, glibc-based system. It is intended for use directly by "mostly-statically compiled" languages like Go, Rust or D.

Statically compiled applications (Go) that do not require libc can use the gcr.io/distroless/static image, which contains:

• ca-certificates
• A /etc/passwd entry for a root user
• A /tmp directory
• tzdata

Most other applications (and Go apps that require libc/cgo) should start with gcr.io/distroless/base, which contains all
of the packages in gcr.io/distroless/static, and

• glibc
• libssl
• openssl