Paramater remove_text in mpl_image_compare decorator does not remove axis labels

[RNKuhns]

When choosing remove_text=True I would have assumed that the text for axis labels was removed along with the axis ticks and any titles. But it doesn't seem to do that.

The code uses remove_ticks_and_titles from matplotlib and that does not appear to remove the axis labels (See matplotlib documentation).

I'd propose updating the remove_text conditional as follows:

if remove_text:
    remove_ticks_and_titles(fig)
    for ax in fig.get_axes():
        ax.set_xlabel = ""
        ax.set_ylabel = ""

If this seems reasonable, I can submit a PR.