Added Docker labels
This merge request adds labels to Docker images produced by CI and manual invocations of build_instance.sh script.
It also updates the CI to check if the pipeline is run for a Git tag - and if so to additionally tag the resulting HAfAH Docker image with that Git tag (eg: https://gitlab.syncad.com/hive/HAfAH/-/jobs/994831).
This creates a one-to-one relationship between Git And Docker tags - although it's still possible to arbitrally add Docker tags by pulling or building an image locally, tagging it and pushing it to the repository.
Edited by Konrad Botor