Base docker image for CI

Create a pre-build stage in CI which creates a docker image with the build dependencies pre-loaded. This will upload to the project container registry if possible, docker hub if not, and update when dependencies change. This will speed up CI, which is relevant as the project grows and possibly integrates an S3 layer.

Questions:

• Can we maintain a non-llvm rocky8 and use a thinner image for static analysis?
• Can we move catch2, nlohmann-json, and other dependencies from the build to the image?
• How will the possible merge with OSTK and deimos affect this?