Add missing action_limit settings and new policy_limit settings

[michel-laterman]

action_limit was added as part of elastic/fleet-server#2994 which i think made it into 8.12.0
policy_limit is a part of elastic/fleet-server#3008 which is new

[github-actions]

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[mergify]

This pull request does not have a backport label. Could you fix it @michel-laterman? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-/d./d is the label to automatically backport to the /d./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[kilfoyle]

LGTM! Thanks for adding these @michel-laterman. I'll merge this once the CI checks pass.