Refactor `AbstractSimpleTransportTestCase` and `MockTransportService` to not use `Version.transportVersion` 
modules/transport-netty4/src/test/java/org/elasticsearch/transport/netty4/SimpleNetty4TransportTests.java
assertThat(keepInterval, lessThanOrEqualTo(500));
    }
    public void testTimeoutPerConnection() throws IOException {
        assumeTrue("Works only on BSD network stacks", Constants.MAC_OS_X || Constants.FREE_BSD);
        try (ServerSocket socket = new MockServerSocket()) {
            
            
            
            
            
            
            
            socket.bind(getLocalEphemeral(), 1);
            socket.setReuseAddress(true);
            DiscoveryNode first = new DiscoveryNode(
                "TEST",
                new TransportAddress(socket.getInetAddress(), socket.getLocalPort()),
                emptyMap(),
                emptySet(),
                version0
            );
            DiscoveryNode second = new DiscoveryNode(
                "TEST",
                new TransportAddress(socket.getInetAddress(), socket.getLocalPort()),
                emptyMap(),
                emptySet(),
                version0
            );
            ConnectionProfile.Builder builder = new ConnectionProfile.Builder();
            builder.addConnections(