relax help_all output check

traitlets may change small details of section headings. Don't worry about them too much

IPython/testing/tools.py

@@ -463,6 +463,6 b" def help_all_output_test(subcommand=''):"
     nt.assert_equal(rc, 0, err)
     nt.assert_not_in("Traceback", err)
     nt.assert_in("Options", out)
-    nt.assert_in("Class parameters", out)
+    nt.assert_in("Class", out)
     return out, err