[FEATURE] Support steps to newsrec models

[loomlike]

Description

Currently newsrec models only support epoch training and the smoke-tests with epoch = 1 take minutes for each notebook.
With a simple tweak to base_model.fit(), we can introduce steps parameters that constraint the number of batches to train.
Then, we can set steps = 1 to the smoke test which will expediate the test time.

Expected behavior with the suggested feature

Use steps = 1 to all the smoke tests of the newsrec models.