Incorrect assertion in cs120_lab3_ctr_df.dbc (5f)

[marcindulak]

Concerns 8252845

Following the discussion at https://piazza.com/class/iqfbu516yuj5t3?cid=653
it seems that "expected_test_baseline = 0.530363901139" used in the assertion comes from hash_test_df instead of hash_train_df