Separate test & lint and container build workflows for actions so that they can be triggered separately

[rascasoft]

Creating two workflow yml files instead of one, we can have kpa_generator trigger just the container build, since there's no big deal in having the lint and test repeated with no code changes and everything should become faster.

[rascasoft]

Have a look at this https://stackoverflow.com/questions/62750603/github-actions-trigger-another-action-after-one-action-is-completed specifically on the section:

2. Separate workflow, using the workflow_run event as a trigger

Creating a yaml with:

# Only trigger, when the build workflow succeeded
on:
  workflow_dispatch:
  workflow_run:
    workflows: ["CI build"]
    types:
      - completed

So with both workflow_dispatch: and workflow_run: should do the trick.