[Spike] Investigate Quarkus Improvements in Unified Push

The team has been investigating how and if running in a quarkus environment will be beneficial to UnifiedPush when running in a k8s environment. This spike will answer questions such as 
 * How much effort will it take to port the REST endpoints into Quarkus?

 * Can we make each push sender a Quarkus microservice?

 * What changes to our docker-compose script will be needed?¹

 * What changes to the operator will be needed?²

 * What will the update process look like?

1 Docker-compose is used for local development.

2 The operator is responsible for maintaining the k8s environment. (https://github.com/aerogear/unifiedpush-operator)