Additional fields to validate (?)

[laurentsimon]

container, run, services, environment and the workflow-call trigger could be checked for.
To be clear, none of these are valid in a job that calls a re-usable workflow. env, default, steps and runs-on are not valid either (even though I've asked checks for it) so we may as well remove them in the future. The top defaults and env don't propagate to re-usable workflows either.

The only field we really need to validate is the permissions field.

[laurentsimon]

my follow-up question is: shall we remove checks for all these fields and only keep the permission validation?

[laurentsimon]

cc @asraa