Feature request: Add pre-build image to container registry

[nikstuckenbrock]

Describe the solution you'd like
Pre-build container image like here

[pascaliske]

@nikstuckenbrock The implementation should be straightforward. Probably just an additional block inside the publish.yml workflow. I will try to prepare a PR...

[q2dg]

Please! There is already the Cyberchef image in ghcr.io/gchq so i'd be terrific having Cyberchef-server image there too.