linestyle argument in overlpot_points

OS: Ubuntu
Python Version: 3.9
Corner Version: v2.2.2

I've found a tiny, probably inconsequential bug in overplot_points related to passing the argument ls to change the linestyle

import corner
import numpy as np

ndim, nsamples = 2, 10000
np.random.seed(42)
samples = np.random.randn(ndim * nsamples).reshape([nsamples, ndim])
figure = corner.corner(samples)

val = np.mean(samples, axis=0)
corner.overplot_points(figure, val[None], ls="--")

This gives the error: TypeError: Got both 'ls' and 'linestyle', which are aliases of one another

I expected that this wouldn't give an error, and should be the same as calling replacing ls with linestyle in the call to overplot_points (which doesn't seem to affect the plot anyways).

I think the solution is to remove the line kwargs["linestyle"] = kwargs.pop("linestyle", "none") in the definition of overplot_points in src/corner/core.py. With this line gone, I no longer get this error and all tests are passed when running nox.

This is a small fix but I'd be happy to open a PR for it.

Start in src/corner/core.py at the overplot_points definition, focusing on how linestyle-related keyword arguments are handled. Reproduce the reported call with ls="--", then run nox and confirm that overplot_points accepts the alias without raising the duplicate-alias TypeError and that the existing tests still pass.