auto-t: fix testDPP after Stop() change

Stop() will now return NotFound if DPP is not running. This causes
the DPP test to fail since it calls this regardless if the protocol
already stopped. Ignore this exception since tests end in various
states, some stopped and some not.

autotests/testDPP/connection_test.py

@@ -148,8 +148,13 @@ class Test(unittest.TestCase):
         self.rule0.drop = True
 
     def tearDown(self):
-        self.device.disconnect()
-        self.device.dpp_stop()
+        # Tests end in various states, don't fail when tearing down.
+        try:
+            self.device.disconnect()
+            self.device.dpp_stop()
+        except:
+            pass
+
         self.wpas.dpp_configurator_remove()
         self.wpas.clean_up()