Null state text for announcements view

bookwyrm/templates/settings/announcements.html

@@ -14,6 +14,7 @@
     {% include 'settings/announcement_form.html' with controls_text="create_announcement" %}
 </form>
 
+<div class="block">
     <table class="table is-striped">
         <tr>
             <th>
@@ -49,5 +50,10 @@
         {% endfor %}
     </table>
 
+    {% if not announcements %}
+    <p><em>{% trans "No announcements found." %}</em></p>
+    {% endif %}
+</div>
+
 {% include 'snippets/pagination.html' with page=announcements path=request.path %}
 {% endblock %}