net-test: close() fixes for resilient_rs_test.py

Test: on UML
Signed-off-by: Maciej ┼╗enczykowski <maze@google.com>
Change-Id: I74d10acf1f8f651c89aea5edca7f1ffce4f57aa1
diff --git a/net/test/resilient_rs_test.py b/net/test/resilient_rs_test.py
index f6e022b..f53217d 100755
--- a/net/test/resilient_rs_test.py
+++ b/net/test/resilient_rs_test.py
@@ -171,5 +171,7 @@
       self.assertLess(min_exp, t)
       self.assertGreater(max_exp, t)
 
+    tun.close()
+
 if __name__ == "__main__":
   unittest.main()