add assert to check if one element exists before click on checkout inside this element

bt5/erp5_ui_test/PathTemplateItem/portal_tests/relation_field_zuite/testRelationFieldColumns.xml

@@ -231,7 +231,11 @@
   <td>Relative URL</td>\n
 </tr>\n
 </tal:block>\n
-\n
+<tr>\n
+  <td>verifyElementPresent</td>\n
+  <td>//*[@class=\'listbox-data-line-0 DataA\']/*[@class="listbox-table-select-cell"]</td>\n
+  <td>Category</td>\n
+</tr>\n
 <tr>\n
   <td>click</td>\n
   <td>//*[@class=\'listbox-data-line-0 DataA\']/*[@class="listbox-table-select-cell"]/input[@type="checkbox"]</td>\n

bt5/erp5_ui_test/bt/revision

-688
+689
\ No newline at end of file