ui: Fix sorting playbook results by date and duration

It used to be that sort_by_date and sort_by_duration accepted a
"form_url" argument before 1.7.0 but it is no longer the case.

Like the playbook list, use an in-line form element instead.

ara/ui/templates/partials/tables/playbook_results.html

@@ -27,8 +27,12 @@ <h4>
                 <tr style="height:50px;">
                   <th class="report-column">Report</th>
                   <th class="medium-status-column">Status</th>
-                  <th class="date-column">{% include "partials/sort_by_date.html" with arg="started" form_url="ui:playbook" %}</th>
-                  <th class="duration-column">{% include "partials/sort_by_duration.html" with form_url="ui:playbook" %}</th>
+                  <th class="date-column">
+                    <form action="{% url 'ui:playbook' playbook.id %}" method="get">{% include "partials/sort_by_date.html" with arg="started" %}</form>
+                  </th>
+                  <th class="duration-column">
+                    <form action="{% url 'ui:playbook' playbook.id %}" method="get">{% include "partials/sort_by_duration.html" %}
+                  </th>
                   <th>Host</th>
                   <th>Action</th>
                   <th>Task</th>
@@ -118,4 +122,4 @@ <h3>No results found matching your query: try <a href='{% url "ui:playbook" play
     </div>
   </div>
 </div>
-<br/>
+<br/>