Make _thread_list_template.html safe.

lms/templates/discussion/_thread_list_template.html

+<%page expression_filter="h"/>
 <%! from django.utils.translation import ugettext as _ %>
 <script type="text/template" id="thread-list-template">
     <div class="forum-nav-header">
@@ -40,7 +41,8 @@
                         <option value="flagged">${_("Flagged")}</option>
                     %endif
                 </select>
-            </label>${"<% if (isCohorted && isPrivilegedUser) { %>"}<label class="forum-nav-filter-cohort">
+            ## safe-lint: disable=python-parse-error,python-wrap-html
+            </label>${"<% if (isCohorted && isPrivilegedUser) { %>" | n, decode.utf8}<label class="forum-nav-filter-cohort">
                 ## Translators: This labels a cohort menu in forum navigation
                 <span class="sr">${_("Cohort:")}</span>
                 <select class="forum-nav-filter-cohort-control">
@@ -49,7 +51,8 @@
                             <option value="${c['id']}">${c['name']}</option>
                         %endfor
                 </select>
-            </label>${"<% } %>"}<label class="forum-nav-sort">
+            ## safe-lint: disable=python-parse-error,python-wrap-html
+            </label>${"<% } %>" | n, decode.utf8}<label class="forum-nav-sort">
                 ## Translators: This labels a sort menu in forum navigation
                 <span class="sr">${_("Sort:")}</span>
                 <select class="forum-nav-sort-control">