make position and options level treeview match in size

Change-Id: I3e9216e95c845a319fc7315f80e926023ddd911b
Reviewed-on: https://gerrit.libreoffice.org/61292
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

cui/uiconfig/ui/numberingoptionspage.ui

@@ -92,7 +92,6 @@
                   <object class="GtkTreeView" id="levellb">
                     <property name="visible">True</property>
                     <property name="can_focus">True</property>
-                    <property name="hexpand">True</property>
                     <property name="vexpand">True</property>
                     <property name="model">liststore1</property>
                     <property name="headers_visible">False</property>