How to update the build image

The procedure is:

1. Update build-image/Dockerfile
2. Create a PR to master with that changed, after the PR is merged to master, the new build image is available in the quay.io repository. Check github action logs here for to find the image tag.
3. Create another PR to replace the image tag in .github/workflows/* (there may be multiple references) and Makefile (variable LATEST_BUILD_IMAGE_TAG).
4. If you are updating Go's runtime version be sure to change actions/setup-go's go-version in ``.github/workflows/*`.
5. Open a PR and make sure the CI with new build-image passes