[tvm4j] disable proxy test for now (#307)

jvm/core/src/test/java/ml/dmlc/tvm/rpc/RPCTest.java

@@ -20,6 +20,7 @@ package ml.dmlc.tvm.rpc;
 import ml.dmlc.tvm.Function;
 import ml.dmlc.tvm.Module;
 import ml.dmlc.tvm.TVMValue;
+import org.junit.Ignore;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -96,6 +97,9 @@ public class RPCTest {
     }
   }
 
+  @Ignore("Proxy server may not have been ready when this test runs,"
+        + " will add retry when callback function can deal with Java exception."
+        + " After that we'll enable this test.")
   @Test
   public void test_connect_proxy_server() {
     String proxyHost = System.getProperty("test.rpc.proxy.host");