knowledge_pad_ui_test: use an RSS from erp5.com for the test

Test should not depend on external websites, we already use erp5.com for
some other tests, so let's use it also for RSS.

/reviewed-on nexedi/erp5!1028

bt5/erp5_knowledge_pad_ui_test/PathTemplateItem/portal_tests/gadgets_zuite/testFeedReaderGadget.zpt

@@ -56,7 +56,7 @@
   <td>Please enter a valid Rss or Atom url in the preference form</td>
   <td></td>
 </tr>
-<!-- Set an URL of ERP5 so test do not depend on external RSS provider (https://www.lemonde.fr/rss/une.xml) -->
+<!-- Set an URL of ERP5 so test do not depend on external RSS provider -->
 <tr>
   <td>click</td>
   <td>//div[@id='${erp5_rss_box_id}']/h3/span/a[2]</td>
@@ -65,7 +65,7 @@
 <tr>
   <td>type</td>
   <td>gadget_preference_${erp5_rss_box_id}_field_my_preferred_rss_feed</td>
-  <td>https://www.lemonde.fr/rss/une.xml</td>
+  <td>https://www.erp5.com/news/WebSection_viewLatestContentListAsRSS</td>
 </tr>
 <tr>
   <td>keyPressAndWait</td>
@@ -79,7 +79,7 @@
 </tr>
 <tr>
   <td>waitForTextPresent</td>
-  <td>Le Monde.fr</td>
+  <td>Press Area</td>
   <td></td>
 </tr>
 <!-- listbox-container  gadget-rss-reader-logo-->