Trainingportal and include/exclude support for multi-workshop action

[jorgemoralespou]

• Fixing the fact that trainingportal.yaml was not released. Fixes When have resources/trainingportal.yaml in multiple workshop repo, is not released. #9
  • Adds a warning if trainingportal file is not found
• Adding support for include/exclude workshops in release. Trainingportal.yaml file contents will not add/remove workshops, so whatever is in there, will be released. Fixes Add new GitHub action for publishing multiple workshops from a repository. #2
• Removes depedency on Carvel tools as it now uses educates CLI from educates-cli image via Docker.

This PR targets v7 of the action. You can decide if this should be a new version though.

Tested on this repository https://github.com/jorgemoralespou/labs-vcluster-testing/actions