Remove batch_size when doing stepwise fit
`batch_size` is always `None` , because `steps_per_epoch` and `batch_size` are mutually exclusive.
Passing batch_size seems irrelevant as `None` is its default value in `test_loop`
@@ -157,7 +157,6 @@ def fit_loop(model, f, ins,
if do_validation:
val_outs = test_loop(model, val_f, val_ins,
- batch_size=batch_size,
steps=validation_steps,
verbose=0)
if not isinstance(val_outs, list):
