That's basically what App Engine Flexible [0] is. It's yet to reach General Availability, but all you have to do is define a bunch of containers and a dispatch.yaml file [1], and App Engine then takes care of deploying/routing/scheduling it for you.
This sounds useful and revived my interest in GAE. The Go example has health check code. It makes sense. Are there equivalent offerings from AWS and Azure? This looks likes a unique GAE feature.