Add GKE Autopilot instructions (#588)
Add GKE Autopilot instructions (#588)

* add gke autopilot mode

* edits

* streamlined content
GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo