[Data checks] Fix missing margin for solve buttons

aleksis/core/static/style.scss

@@ -543,6 +543,10 @@ main .alert p:first-child, main .alert div:first-child {
   height: 100%;
 }
 
+.btn-margin {
+  margin-bottom: 5px;
+}
+
 
 /* Dashboard */
 

aleksis/core/templates/core/data_check/list.html

@@ -64,7 +64,8 @@
               </td>
               <td>
                 {% for option_name, option in result.related_check.solve_options.items %}
-                  <a class="btn waves-effect waves-light" href="{% url "data_check_solve" result.pk option_name %}">
+                  <a class="btn btn-margin waves-effect waves-light"
+                     href="{% url "data_check_solve" result.pk option_name %}">
                     {{ option.verbose_name }}
                   </a>
                 {% endfor %}