tests/tcp: Use server.wait_closed() to avoid ResourceWarnings

Author: 1st1

tests/test_tcp.py

@@ -117,6 +117,7 @@ async def start_server_sock():
                 TIMEOUT, loop=self.loop)
 
             srv.close()
+            await srv.wait_closed()
 
             # Check that the server cleaned-up proxy-sockets
             for srv_sock in srv_socks:
@@ -183,7 +184,9 @@ async def runner():
             srv = await self.loop.create_server(
                 asyncio.Protocol,
                 None, port)
+
             srv.close()
+            await srv.wait_closed()
 
         self.loop.run_until_complete(runner())
 
@@ -213,6 +216,9 @@ async def runner():
             srv1.close()
             srv2.close()
 
+            await srv1.wait_closed()
+            await srv2.wait_closed()
+
         self.loop.run_until_complete(runner())
 
     def test_create_connection_1(self):