Gets the `PangoLayout` used to display the label.
The layout is useful to e.g. convert text positions to pixel positions, in combination with [method@Gtk.Label.get_layout_offsets]. The returned
layout is owned by the
label so need not be freed by the caller. The
label is free to recreate its layout at any
time, so it should be considered read-only.
the [class@Pango.Layout] for this label