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Asserts the channel has not pushed a message to the client
matching the given event and payload within `timeout`.

Like `assert_push`, the event and payload are patterns.

The timeout is in milliseconds and defaults to 100ms.
Keep in mind this macro will block the test by the
timeout value, so use it only when necessary as overuse
will certainly slow down your test suite.
Please help! Open an issue on GitHub if this assessment is incorrect.