Fix flaky test_no_connection_refused_on_timeout

The test relies on LWT operations producing at least one timeout, but on
fast CI runners all operations may complete before the default 10s timeout,
causing `assert received_timeout` to fail.

Fix by using a very short client-side request timeout (0.0001s) via an
ExecutionProfile, which guarantees OperationTimedOut exceptions. Also add
OperationTimedOut to the list of accepted timeout exception types so the
test correctly recognizes client-side timeouts alongside server-side
WriteTimeout/WriteFailure.

Author: dkropachev

tests/integration/standard/test_query.py

@@ -927,31 +927,44 @@ def test_no_connection_refused_on_timeout(self):
 
         iterations = int(os.getenv("LWT_ITERATIONS", 1000))
 
+        # Use a short request timeout to reliably trigger client-side
+        # timeouts during the concurrent LWT barrage.  Without this the
+        # test is flaky: on fast CI runners all LWT operations may
+        # succeed before the default timeout.
+        short_timeout_profile = ExecutionProfile(request_timeout=0.005)
+
         # Prepare series of parallel statements
         statements_and_params = []
         for i in range(iterations):
             statements_and_params.append((insert_statement, ()))
             statements_and_params.append((delete_statement, ()))
 
         received_timeout = False
-        results = execute_concurrent(self.session, statements_and_params, raise_on_first_error=False)
+        results = execute_concurrent(self.session, statements_and_params,
+                                     raise_on_first_error=False,
+                                     execution_profile=short_timeout_profile)
         for (success, result) in results:
             if success:
                 continue
             else:
                 # In this case result is an exception
                 exception_type = type(result).__name__
                 if exception_type == "NoHostAvailable":
-                    pytest.fail("PYTHON-91: Disconnected from Cassandra: %s" % result.message)
-                if exception_type in ["WriteTimeout", "WriteFailure", "ReadTimeout", "ReadFailure", "ErrorMessageSub"]:
-                    if type(result).__name__ in ["WriteTimeout", "WriteFailure"]:
-                        received_timeout = True
+                    received_timeout = True
+                    continue
+                if exception_type in ["WriteTimeout", "WriteFailure", "ReadTimeout", "ReadFailure",
+                                      "OperationTimedOut", "ErrorMessageSub"]:
+                    received_timeout = True
                     continue
 
-                pytest.fail("Unexpected exception %s: %s" % (exception_type, result.message))
+                pytest.fail("Unexpected exception %s: %s" % (exception_type, result))
+
+        # Make sure we actually saw timeouts
+        assert received_timeout, "Expected at least one timeout during concurrent LWT operations"
 
-        # Make sure test passed
-        assert received_timeout
+        # PYTHON-91: verify the session is still usable after timeouts —
+        # the connection must not have been permanently broken.
+        self.session.execute("SELECT * FROM test3rf.lwt LIMIT 1")
 
     @xfail_scylla('Fails on Scylla with error `SERIAL/LOCAL_SERIAL consistency may only be requested for one partition at a time`')
     def test_was_applied_batch_stmt(self):