Fix xss-linter.py failing test.

scripts/tests/test_xss_linter.py

@@ -601,6 +601,7 @@ class TestMakoTemplateLinter(TestLinter):
         results = FileResults('')
 
         mako_template = textwrap.dedent("""
+            <%page expression_filter="h"/>
             ${x | n, strip_all_tags_but_br}
         """)