Container-based procedure worker

Description

• Adds ContainerProcedureWorker which starts a podman container to run procedures in
• Adds a Containerfile for the requirements for a bec deployment, and one which builds on that for the local deployment
• Auto-builds the worker container on first use
• Adds support for integer enums generically to BECMessage serialization to allow status messages from the container without special casing them again
• Adds a CI step to push a container image with the requirements for BEC (but not bec itself) to giea:
  • Tested on the branch e.g. https://gitlab.psi.ch/bec/bec/-/jobs/381957 https://gitea.psi.ch/bec/-/packages https://gitea.psi.ch/bec/-/packages/container/bec_procedure_requirements/3.33.0a1 then modified to only run on new versions
• Adds e2e test for local execution - have podman installed and run the systemd podman.socket service for it to work

TODO (in new issue? / MR) - get e2e running in CI - will require some infra changes