make example client renew connectin every two seconds for debugging

examples/client_to_prosys_crypto.py

@@ -9,11 +9,13 @@ from asyncua import Client
 async def main():
     client = Client("opc.tcp://localhost:53530/OPCUA/SimulationServer/")
     client.set_security_string("Basic256Sha256,Sign,certificate-example.der,private-key-example.pem")
+    client.session_timeout = 2000
     async with client:
         root = client.nodes.root
         objects = client.nodes.objects
-        print("childs og objects are: ", await objects.get_children())
-        await asyncio.sleep(3)
+        while True:
+            print("childs og objects are: ", await objects.get_children())
+            await asyncio.sleep(1)