Update workspaces image platform

What does this MR do and why?

The default Platform is linux/arm64 for workspace node, and this is causing the local workspace image pull failure, and i am updating and fixing this.

  OS Image:                   Alpine Linux v3.19
  Operating System:           linux
  Architecture:               arm64

 Failed to pull image "registry.gitlab.com/gitlab-org/gitlab-build-images/workspaces/ubuntu-24.04:golang-1.23": rpc error: code = NotFound desc = failed to pull and unpack image "registry.gitlab.com/gitlab-org/gitlab-build-images/workspaces/ubuntu-24.04:golang-1.23": no match for platform in manifest: not found

Checklist

• (If applicable) Add patches if required for upgrading Ruby version in https://gitlab.com/gitlab-org/gitlab-build-images/-/tree/master/patches/ruby.