Update DeployStack to use `main` branch (#1225)
Update DeployStack to use `main` branch (#1225)

* Update DeployStack to use main branch

* Remove branch since default is main
GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo,GoogleCloudPlatform/microservices-demo