Create JupyterHub Image with Rucio Extension

[goseind]

The extension is installed in the single-user image for JHub and needs manual configuration within JHub for OIDC authentication.

• Create a docker image with the extension installed and add the Rucio config
• Create GH Actions for images
• Write script for OIDC token generation
• Add EOS RSE with authentication (replica mode)
• Test view and file operations in JHub

upstream issue/PRs: rucio/jupyterlab-extension#20

[goseind]

The image is here: ghcr.io/goseind/singleuser-base and needs to be moved to the vre orga (cascading form base image, as done by @garciagenrique with the ops images).