VSN columns does not work with pandas index

[aretaon]

Describe the bug
When supplying a pandas column index for pp.vsn column, the UID string is appended to all col names instead of being added to the list.

To Reproduce

pg, s1_cols = pp.vsn(
    pg,
    pg.filter(regex="^sum_iBAQ.*S1_R\d+_median_corrected$").columns,
    return_cols=True,
)

returns

KeyError: "None of [Index(['sum_iBAQ TPA_S1_R1_median_correctedUID',\n 'sum_iBAQ WT_S1_R1_median_correctedUID',\n 'sum_iBAQ WT_S1_R2_median_correctedUID',\n 'sum_iBAQ WT_S1_R3_median_correctedUID',\n 'sum_iBAQ TPA_S1_R2_median_correctedUID',\n 'sum_iBAQ TPA_S1_R3_median_correctedUID'],\n dtype='object')] are in the [columns]"

Expected behavior
There should be an error when calling vsn with the wrong column dtype indicating to supply a list.