Add CI configuration that would build ready-to-use containers for all major platforms

[SoapHia]

Add CI configuration (GithubActions or CloudBuild) that would build ready-to-use containers for all major platforms (e.g. linux/amd64, linux/arm, linux/arm64)

• Tag images with:

  • full version (e.g. 1.0.2)
  • minor version (e.g. 1.0)
  • major version (e.g. 1)
  • latest git ref (e.g. git rev-parse --short HEAD)
  • Build ID for debugging/tracking purposes

• Cross compile images for linux/amd64, linux/arm, linux/arm64

[SoapHia]

Cross-platform images are WIP on a forked repository, but de-prioritised due to multiple errors in the build pipeline.

I attempted to build the images using buildx for linux/amd64, linux/arm, linux/arm64, but the arm platforms encountered the following issues:

• Unsupported syscall errors on Alpine, but builds ok on Buster. This is undesired as using Buster may introduce additional vulnerabilities and make images unnecessarily large
• takes a very long time to build (20+ minutes) when on default cloud build machine

We attempted to mitigate the above issues by changing the machine type to be of 8CPUs, but this resulted in segmentation faults for arm/v7 builds.

The current solution in the above branch only works for building linux/amd64 and linux/arm64 on Alpine with 8 CPUs. In the future, the segmentation fault will be fixed so that builds can be completed for other platforms.