Refactor `AbstractSimpleTransportTestCase` and `MockTransportService` to not use `Version.transportVersion` 
x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/transport/netty4/SimpleSecurityNetty4ServerTransportTests.java
listener.onResponse(TransportVersionUtils.minimumCompatibilityVersion(version));
                }
            }
        };
    }
    private SSLService createSSLService() {
        return createSSLService(Settings.EMPTY);
    }
    protected SSLService createSSLService(Settings settings) {
        Path testnodeCert = getDataPath("/org/elasticsearch/xpack/security/transport/ssl/certs/simple/testnode.crt");
        Path testnodeKey = getDataPath("/org/elasticsearch/xpack/security/transport/ssl/certs/simple/testnode.pem");
        MockSecureSettings secureSettings = new MockSecureSettings();
        secureSettings.setString("xpack.security.transport.ssl.secure_key_passphrase", "testnode");
        
        secureSettings.setString("transport.profiles.client.xpack.security.ssl.secure_key_passphrase", "testnode");
        
        secureSettings.setString("xpack.security.remote_cluster_server.ssl.secure_key_passphrase", "testnode");
        Settings settings1 = Settings.builder()
            .put("xpack.security.transport.ssl.enabled", true)
            .put("xpack.security.transport.ssl.key", testnodeKey)
            .put("xpack.security.transport.ssl.certificate", testnodeCert)
            .put("path.home", createTempDir())
            .put(settings)
            .setSecureSettings(secureSettings)
            .build();
        try {
            return new SSLService(TestEnvironment.newEnvironment(settings1));
        } catch (Exception e) {
            throw new RuntimeException(e);
        }