Fix behat test for Teachers can view low grade report and send a message

renderer.php

@@ -896,7 +896,7 @@ class mod_attendance_renderer extends plugin_renderer_base {
             }
 
             if ($bulkmessagecapability) { // Create the checkbox for bulk messaging.
-                $row->cells[] = html_writer::checkbox('user'.$user->id, 'on', false);
+                $row->cells[] = html_writer::checkbox('user'.$user->id, 'on', false, '', array('class' => 'attendancesesscheckbox'));
             }
 
             $table->data[] = $row;

tests/behat/attendance_mod.feature

@@ -66,7 +66,7 @@ Feature: Teachers and Students can record session attendance
         And I click on "id_submitbutton" "button"
         And I follow "Report"
         And I follow "Low grade"
-        And I set the field "user3" to "1"
+        And I set the field "cbselector" to "1"
         And I click on "Send a message" "button"
         Then I should see "Message body"
         And I should see "student1@asd.com"