As discussed in T294419#7688032, the revscoring transformer architecture introduces a ton of overhead complexity that is unecessary at this point.
Let's revert back to the predictor-only design and move the feature extraction bit to either the predict method or even possibly the preprocess method (which might allow us to experiment with making the call async)
TODO:
- Remove transformer code
- Remove transformer blubber file & remove pipeline config
- Remove transformer jobs from Jenkins (if necessary?)
- Clear out registry for old images (unless we want to keep them around)