Restore the color picker icon in colorwindow.ui

Caused by a bug in Glade.

Change-Id: I8acc923093f7ef1e8a2a5831bc96c63e4c7f0341

svx/uiconfig/ui/colorwindow.ui

@@ -13,7 +13,7 @@
     <property name="can_focus">False</property>
     <property name="margin_right">6</property>
     <property name="xalign">0</property>
-    <property name="pixbuf">cmd/sc_square_unfilled.png</property>
+    <property name="pixbuf">cmd/sc_colorsettings.png</property>
     <property name="icon_size">1</property>
   </object>
   <object class="GtkImage" id="none_icon">