MULE-7809: Removing test for receivebuffersize. The value is just a sugg...

...estion, so the assertion fails on some environments.
We don't know if it will use hint or not no, but there is still value in asserting the expected behaviour that you describe, that the size is either default socket buffer size or configured size.  You might think this is of minimal value, but it covers regressions in HttpConnector/HttpServerConnection where the value of custom receive buffer size is propagated to socket.

assertThat (conn.getSocketReceiveBufferSize(), anyOf(equalTo(RECEIVE_BUFFER_SIZE), equalTo(new Socket(). getReceiveBufferSize)))