boxpctiles does not draw boxes

[AWSisco]

Description

I think there's a minor bug when adding on-the-fly box plots to scatter, line, and bar charts. boxpctile works as expected, but the equivalent boxpctiles has no effect.

Steps to reproduce

import proplot as pplt
import numpy as np
import pandas as pd

data = np.full((100,10),fill_value=np.nan)  

np.random.seed(1999)
mu = np.random.randint(10,21,10)
sigma = np.random.randint(1,5,10)

for i in range(0,10):
    data[:,i] = np.random.normal(mu[i],sigma[i],100)

data = pd.DataFrame(data)

fig, axs = pplt.subplots(ncols=2, aspect=(1.5,1))

axs[0].bar(data, medians=True, barpctile=(5,95), boxpctile=True, ec='k', c='yellow5')
axs[1].bar(data, medians=True, barpctile=(5,95), boxpctiles=True, ec='k', c='yellow5') #No boxes appear here

Proplot version

matplotlib=3.5.2 proplot=0.9.5.post332