Refactor `AbstractSimpleTransportTestCase` and `MockTransportService` to not use `Version.transportVersion` 
x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/transport/netty4/SimpleSecurityNetty4ServerTransportTests.java
doneLatch.await();
                } catch (Exception e) {
                    throw new AssertionError(e);
                } finally {
                    IOUtils.closeWhileHandlingException(acceptedSocket);
                }
            }).start();
            DiscoveryNode dummy = new DiscoveryNode(
                "TEST",
                new TransportAddress(socket.getInetAddress(), socket.getLocalPort()),
                emptyMap(),
                emptySet(),
                version0
            );
            ConnectionProfile.Builder builder = new ConnectionProfile.Builder();
            builder.addConnections(
                1,
                TransportRequestOptions.Type.BULK,
                TransportRequestOptions.Type.PING,
                TransportRequestOptions.Type.RECOVERY,
                TransportRequestOptions.Type.REG,
                TransportRequestOptions.Type.STATE
            );
            builder.setHandshakeTimeout(TimeValue.timeValueMillis(1));
            Settings settings = Settings.builder().put("xpack.security.transport.ssl.verification_mode", "none").build();
            try (MockTransportService serviceC = buildService("TS_C", version0, settings)) {
                ConnectTransportException ex = expectThrows(
                    ConnectTransportException.class,
                    () -> connectToNode(serviceC, dummy, builder.build())
                );