Standardize analyzer images with overridable GO_VERSION

The following discussion from gitlab-org/security-products/analyzers/security-code-scan!59 (merged) should be addressed:

• @dsearles started a discussion: (+3 comments)

  @theoretick this was hardcoded so as to ensure that we have reproducible builds. If we expose this ARG, then updating https://gitlab.com/gitlab-org/security-products/ci-templates/blob/master/includes-dev/analyzer.yml#L8 will override the go version. I would prefer to see go version in git history for an analyzer. What do you think?