[ci skip] Fix a doc typo

Close #3595
diff --git a/user_guide_src/source/tutorial/static_pages.rst b/user_guide_src/source/tutorial/static_pages.rst
index 36bcd2d..8ba0486 100644
--- a/user_guide_src/source/tutorial/static_pages.rst
+++ b/user_guide_src/source/tutorial/static_pages.rst
@@ -74,7 +74,7 @@
 
             <em>&copy; 2014</em>
         </body>
-    <html>
+    </html>
 
 Adding logic to the controller
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