erp5_payroll: Pay Sheet Cells should be simple Invoice Cells

bt5/erp5_payroll/PortalTypeTemplateItem/portal_types/Pay%20Sheet%20Cell.xml

@@ -45,11 +45,15 @@
         </item>
         <item>
             <key> <string>init_script</string> </key>
-            <value> <string></string> </value>
+            <value>
+              <none/>
+            </value>
         </item>
         <item>
             <key> <string>permission</string> </key>
-            <value> <string></string> </value>
+            <value>
+              <none/>
+            </value>
         </item>
         <item>
             <key> <string>redirect_script</string> </key>
@@ -61,7 +65,19 @@
         </item>
         <item>
             <key> <string>type_class</string> </key>
-            <value> <string>PaySheetCell</string> </value>
+            <value> <string>InvoiceCell</string> </value>
+        </item>
+        <item>
+            <key> <string>type_interface</string> </key>
+            <value>
+              <tuple/>
+            </value>
+        </item>
+        <item>
+            <key> <string>type_mixin</string> </key>
+            <value>
+              <tuple/>
+            </value>
         </item>
       </dictionary>
     </pickle>