Switch base image to new VSCode provided by OpenShift

[computate]

OpenShift is now offering a VSCode OpenShift AI Workbench Image from
quay.io/modh/codeserver:

$ oc --as system:admin -n redhat-ods-applications get imagestream/code-server-notebook -o yaml | grep '  from:' -A 2
    from:
      kind: DockerImage
      name: quay.io/modh/codeserver@sha256:575df4c8ce5bfb2c6dc355fcae74e0cc7499e0490f4d9deeb9788fe3aaa7f6d1

so we will use that instead.

This new image uses an up-to-date code-server: v4.92.2 and Code: 1.92.2

versus code-server: v4.16.1 and Code: 1.80.2 in the old image.

Thanks @Milstein for the suggestion!