feature: Add compile = False argument to bentoml.keras.load_model()

[MarioMarkov]

Feature request

When loading model with bentoml.keras.load_model() a warning is shown: [WARNING] [dev_api_server] No training configuration found in save file, so the model was *not* compiled. Compile it manually., so It would be nice if we can set: compile=False

Motivation

It is annoying and probably will save execution time.

Other

No response