Series.reorder_levels docstring includes extra `axis` argument.

[tschm]

Code Sample, a copy-pastable example if possible

    def reorder_levels(self, order):
        """
        Rearrange index levels using input order. May not drop or duplicate
        levels

        Parameters
        ----------
        order : list of int representing new level order.
               (reference level by number or key)
        axis : where to reorder levels

        Returns
        -------
        type of caller (new object)
        """
        if not isinstance(self.index, MultiIndex):  # pragma: no cover
            raise Exception('Can only reorder levels on a hierarchical axis.')

        result = self.copy()
        result.index = result.index.reorder_levels(order)
        return result

Problem description

[this should explain why the current behaviour is a problem and why the expected output is a better solution.]

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Expected Output

Output of pd.show_versions()

[paste the output of pd.show_versions() here below this line]

[TomAugspurger]

We can update the docs, or add an unused axis to Series.reorder_levels.

If we decide to add axis to Series.reorder_levels, it'll probably be easiest to just move the implementation to NDFrame.reorder_levels and use self._get_axis(axis)

[SandrineP]

I can update the docs for now. I'll go ahead and create a PR.

[jbrockmendel]

Closed by #22734