Reorder imports to address code quality (tox)

Running tox revealed that the "Sync connection tracking and graceful
shutdown" patch introduced "misordered import statements" warning and
unused assignments (client) in "with connect(...) as client:" in the
added tests. This commit addresses these code quality messages.

Author: darkhaniop

tests/sync/test_server.py

@@ -7,13 +7,13 @@
 import time
 import unittest
 
+from websockets import CloseCode
 from websockets.exceptions import (
     ConnectionClosedError,
     ConnectionClosedOK,
     InvalidStatus,
     NegotiationError,
 )
-from websockets import CloseCode, State
 from websockets.http11 import Request, Response
 from websockets.sync.client import connect, unix_connect
 from websockets.sync.server import *
@@ -352,7 +352,7 @@ def test_connections_is_empty_after_disconnects(self):
         """Clients are added to Server._connections, and removed when disconnected."""
         with run_server() as server:
             connections: set[ServerConnection] = server._connections
-            with connect(get_uri(server)) as client:
+            with connect(get_uri(server)):
                 self.assertEqual(len(connections), 1)
             time.sleep(0.5)
             self.assertEqual(len(connections), 0)
@@ -382,7 +382,7 @@ def close(self, code=CloseCode.NORMAL_CLOSURE, reason=""):
         with run_server(create_connection=ServerConnectionWithBrokenClose) as server:
 
             def client():
-                with connect(get_uri(server)) as client:
+                with connect(get_uri(server)):
                     time.sleep(1)
 
             for i in range(CLIENTS_TO_LAUNCH):