accounting: don't include empty item in mirror_section_category in report dialogs

The meaning of an empty item is not really clear

bt5/erp5_accounting/SkinTemplateItem/portal_skins/erp5_accounting/AccountModule_viewDialogFieldLibrary/your_mirror_section_category_list.xml

@@ -263,7 +263,7 @@
       <dictionary>
         <item>
             <key> <string>_text</string> </key>
-            <value> <string>python:here.portal_categories.role.getCategoryChildTranslatedLogicalPathItemList(base=True)</string> </value>
+            <value> <string>python:here.portal_categories.role.getCategoryChildTranslatedLogicalPathItemList(base=True, display_none_category=False)</string> </value>
         </item>
       </dictionary>
     </pickle>