erp5_travel_expense: fix permission issue

temporairy solution

bt5/erp5_travel_expense/SkinTemplateItem/portal_skins/erp5_hr_request/ExpenseValidationRequest_createPurchaseTransaction.xml

@@ -52,6 +52,15 @@
             <key> <string>_params</string> </key>
             <value> <string></string> </value>
         </item>
+        <item>
+            <key> <string>_proxy_roles</string> </key>
+            <value>
+              <tuple>
+                <string>Manager</string>
+                <string>Owner</string>
+              </tuple>
+            </value>
+        </item>
         <item>
             <key> <string>id</string> </key>
             <value> <string>ExpenseValidationRequest_createPurchaseTransaction</string> </value>