Hiding only axis labels when plotting using wcs as projection

From the astropy slack:

The [astropy doc](https://docs.astropy.org/en/stable/visualization/wcsaxes/ticks_labels_grid.html) only shows how to hide the ticks, but with the ticks the labels are also hidden.

If I only want to hide the axis labels and not the tick labels, I would expect to use `ax[1][1].coords[1].set_axislabel("")`. However,
I'm still getting pos.eq.dec as labels on the plot, and if I do `ax[1][1].coords[1].set_ticklabel_visible(False)` then the y axis label disappears and the tick labels also disappear.

The temporal solution to this is adding an space instead of an empty string e.g `ax[1][1].coords[1].set_axislabel(" ")`.

Start with the WCSAxes ticks, labels, and grid documentation and reproduce the behavior using ax[1][1].coords[1].set_axislabel("") and set_ticklabel_visible(False). Trace how the coordinate axis label visibility is handled, then verify that an empty axis-label string hides only that label while tick labels remain visible.

Written by the indexing model from the issue text.