erp5_document_scanner: add Manager proxy role to script

for Base_getDocumentScannerDefaultBackendDataAsJSON
since we need to be able to create Active Process

bt5/erp5_document_scanner/SkinTemplateItem/portal_skins/erp5_document_scanner/Base_getDocumentScannerDefaultBackendDataAsJSON.py

+# Manager Role, to be able to create Active Process
+from zExceptions import Unauthorized
 import json
 
+if REQUEST is not None:
+  raise Unauthorized
 active_process = context.getPortalObject().portal_activities.newActiveProcess(
   reference=context.Base_getDocumentScannerDefaultReference())
 

bt5/erp5_document_scanner/SkinTemplateItem/portal_skins/erp5_document_scanner/Base_getDocumentScannerDefaultBackendDataAsJSON.xml

@@ -50,7 +50,15 @@
         </item>
         <item>
             <key> <string>_params</string> </key>
-            <value> <string></string> </value>
+            <value> <string>REQUEST=None</string> </value>
+        </item>
+        <item>
+            <key> <string>_proxy_roles</string> </key>
+            <value>
+              <tuple>
+                <string>Manager</string>
+              </tuple>
+            </value>
         </item>
         <item>
             <key> <string>id</string> </key>