Clean up code used for preprocess and postprocess docker images

[stinebuu]

The code used for preprocess and postprocess docker images should be cleaned up. Some improvements:

• The tests should run when we create a PR and push to the PR (fixed with Clean up transition code #195)
• make_predictions have a from .utils import *, we should import the methods needed instead of importing everything (fixed with Clean up transition code #195)
• sort functions in utils.py so that the ones imported elsewhere is at top of the file, and add underscore to private functions (fixed with Clean up transition code #195)
• add some formatting tests? (fixed with Clean up transition code #195)
• make_predictions use form_config, can we use field_config from the model?