Change pipeline to push to quay.io

[GBrawl]

Description of feature

Move away from dockerhub and host images on quay

Purpose of this new feature

Additional information

[GBrawl]

I configured build triggers in quay for stackl-core, stackl-agent and stackl-cli
stackl-opa and stackl-redis have to be pushed manually
you can find the images here https://quay.io/user/stackl