Set kill or restart as default healtcheck action on failure

[jelly]

The default action is to do nothing, which is a bit strange as you went to all the trouble to configure a health check.

• report upstream that the default behaviour does nothing
• determine if we want to either set kill or restart as action or make setting an action mandatory?

Follow up from a comment by @martinpitt in #1233 (review)_

@garrett you might also have some suggestions/opinion on this topic.

[garrett]

Cockpit Podman was instructed to run the container, regardless of healthcheck, so if if a healthcheck fails, it probably makes sense to default to restart. (In other words, the machine should probably keep doing as it was told.)