feat: Improve on the restriction on X and y not to have same columns

[vspinu]

Currently if X and y have common columns the error ValueError: Xandy must not share column names is thrown.

Would it be possible possible to check for common columns in X and y after the recipe has been applied?

Given that Drop and Select would be there, It would make more sense to enforce no column columns after the pipeline has processed, not before.

    import pandas as pd
    import ibis
    import ibis_ml as ml
    con = ibis.duckdb.connect()
    df = pd.DataFrame({
        'cat1': ['AA', 'BBB', 'AA', 'BBB', 'CCC'],
        'cat2': ['X', 'Y', 'Y', 'X', 'Z'],
        'value': [10, 20, 30, 40, 50]
    })
    tbl = con.create_table("tmp", df, overwrite=True)

    tr_oe = ml.Recipe(
        ml.OrdinalEncode(ml.string(), min_frequency=2),
        ml.Drop("value")
    ).fit(tbl, tbl.value)
   # ValueError: `X` and `y` must not share column names