Push the docker images built by ods-quickstarters to DockerHub so we can reuse them when building ODS Boxes.

Is your feature request related to a problem? Please describe.
No, it is not related to a problem.
When the docker images are built by the GitHub actions, please upgrade resulting images to the DockerHub account ( https://hub.docker.com/u/opendevstackorg ), so we can reuse them when building ODS Boxes and reduce time spent in that task (about 5h 30m right now).

Describe the solution you'd like
When the docker images are built for the branches master, 4.x, etc, push them to GitHub with the expected tag (latest, 4.x, etc).

Describe alternatives you've considered

• Using the repository created by Sergio
  https://github.com/opendevstack/ods-docker-images
  which is not working (yet?) and forces us to have in another repository the Dockerfiles. We think they should be here.
• Using docker cache mechanisms, which can not be used because building is done by oc and not directly by docker.
• Reuse the previously created ODS Box and build it incrementally. This could lead us to future problems if upgrades are not done well. Not recommended.

Additional context
For this to work, we need username/password for the DockerHub account, which are currently in other repositories like ods-core, ods-provisioning-app, ods-document-generation-svc, ...
See: https://hub.docker.com/u/opendevstackorg

Start with the GitHub Actions workflows that build the Docker images, then compare the DockerHub credential handling described in ods-core, ods-provisioning-app, and ods-document-generation-svc. Done means images from branches such as master and 4.x are pushed to opendevstackorg with matching tags and can be reused when building ODS Boxes.