Test first release to prod

[raar1]

Following on from issue #172, we now need to try an actual release deployment. This involves tagging the head of the virtual-coach-rasa and niceday_components repos as a release (e.g. v0.5.0) then running the start-prod.yml ansible playbook.

This is so far untested, so it is possible that the release images are not being tagged correctly (if so, check e.g pacakage_rasa.yml and co. in the github actions for the repos.)