Update example to match generator code

[JaimeValdemoros]

Taking https://github.com/letsdiscodev/disco-daemon/blob/588055bf7c865121676b06ab2b1babf810b05b1b/disco/utils/deploymentflow.py#L1003 as a reference:

• "type": "generator" instead of "type": "static"
• publicPath must be set
• Image needs to contain release files at build time
  • Which necessarily means image needs to be built with output files baked in
  • As a result a Dockerfile is required