Submitting a model with same identifier uses previous score

When a model is changed and re-submitted with the same identifier, no new scores will be computed: https://github.com/brain-score/brain-score/blob/67e4d01f78634fd5c38ae0668f37d0e5555746db/brainscore/submission/evaluation.py#L109-L112
Rather, the previously computed scores will be reported back.
We should just re-compute at this point and use the most recent submission in the display.