Improve pipeline workflow
The current pipeline carries a lot of overhead in unnecessary image builds and only supports one merge request at a time. All base images (e.g. nox, server base, etc.) should only be rebuilt if the associated files are changed. Adding rules to the pipeline will allow us to accomplish this. Currently for the merge requests, the images get built into the same container registry tag. Therefore, if there are multiple merge requests in place there will be potential conflicts in who is building what. Having merge requests build their own server images and having tag expiration rules will help us maintain independent branches while still minimizing container storage.