ANOVA drop_cols not optional

[feliciaschulz]

In function run_anova in src/acore/differential_regulation/init.py: drop_cols is mandatory, does not allow the user to not drop any columns.

Issue is mainly here:

res = pd.DataFrame()
if subject is not None and acore.utils.check_is_paired(df, subject, group):
    paired = True
else:
    paired = False

if len(df[group].unique()) == 2:
    groups = df[group].unique()
    drop_cols = [d for d in drop_cols if d != subject] <-----------------------------------
    res = run_ttest(
        df,
        groups[0],
        groups[1],
        alpha=alpha,
        drop_cols=drop_cols,
        subject=subject,
        group=group,
        paired=paired,
        correction=correction,
        permutations=permutations,
        is_logged=is_logged,
        non_par=non_par,
    )