Refactor `AbstractSimpleTransportTestCase` and `MockTransportService` to not use `Version.transportVersion` 
modules/transport-netty4/src/test/java/org/elasticsearch/transport/netty4/SimpleNetty4TransportTests.java
try (Transport.Connection connection = openConnection(serviceC, serviceD.getLocalDiscoNode(), connectionProfile)) {
                assertThat(connection, instanceOf(StubbableTransport.WrappedConnection.class));
                Transport.Connection conn = ((StubbableTransport.WrappedConnection) connection).getConnection();
                assertThat(conn, instanceOf(TcpTransport.NodeChannels.class));
                TcpTransport.NodeChannels nodeChannels = (TcpTransport.NodeChannels) conn;
                for (TcpChannel channel : nodeChannels.getChannels()) {
                    assertFalse(channel.isServerChannel());
                    assertThat(channel.getProfile(), equalTo(transportProfile));
                }
                assertThat(serviceD.getOriginalTransport(), instanceOf(TcpTransport.class));
                for (TcpChannel channel : getAcceptedChannels((TcpTransport) serviceD.getOriginalTransport())) {
                    assertTrue(channel.isServerChannel());
                    assertThat(channel.getProfile(), equalTo(TransportSettings.DEFAULT_PROFILE));
                }
            }
        }
    }
    private void checkDefaultKeepAliveOptions(TcpChannel channel) throws IOException {
        assertThat(channel, instanceOf(Netty4TcpChannel.class));
        Netty4TcpChannel nettyChannel = (Netty4TcpChannel) channel;
        assertThat(nettyChannel.getNettyChannel(), instanceOf(Netty4NioSocketChannel.class));
        Netty4NioSocketChannel netty4NioSocketChannel = (Netty4NioSocketChannel) nettyChannel.getNettyChannel();
        SocketChannel socketChannel = netty4NioSocketChannel.javaChannel();
        assertThat(socketChannel.supportedOptions(), hasItem(NetUtils.getTcpKeepIdleSocketOption()));
        Integer keepIdle = socketChannel.getOption(NetUtils.getTcpKeepIdleSocketOption());
        assertNotNull(keepIdle);
        assertThat(keepIdle, lessThanOrEqualTo(500));
        assertThat(socketChannel.supportedOptions(), hasItem(NetUtils.getTcpKeepIntervalSocketOption()));
        Integer keepInterval = socketChannel.getOption(NetUtils.getTcpKeepIntervalSocketOption());
        assertNotNull(keepInterval);