[java] Fix the logic of generating TaskID (#2747)

## What do these changes do?
Because the logic of generating `TaskID` in java is different from python's, there are many tests fail when we change the `Ray Core` code.
In this change,  I rewrote the logic of generating `TaskID` in java which is the same as the python's.

In java, we call the native method `_generateTaskId()` to generate a `TaskID` which is also used in python. We change `computePutId()`'s logic too.

## Related issue number
[#2608](https://github.com/ray-project/ray/issues/2608)

java/runtime-dev/src/main/java/org/ray/core/impl/RayDevRuntime.java

@@ -33,7 +33,7 @@ public class RayDevRuntime extends RayRuntime {
 
   private byte[] createLocalActor(String className) {
     UniqueID taskId = WorkerContext.currentTask().taskId;
-    UniqueID actorId = UniqueIdHelper.taskComputeReturnId(taskId, 0, false);
+    UniqueID actorId = UniqueIdHelper.computeReturnId(taskId, 0);
     try {
       Class<?> cls = Class.forName(className);
 

java/runtime-dev/src/main/java/org/ray/spi/impl/MockLocalScheduler.java

@@ -89,6 +89,11 @@ public class MockLocalScheduler implements LocalSchedulerLink {
 
   }
 
+  @Override
+  public UniqueID generateTaskId(UniqueID driverId, UniqueID parentTaskId, int taskIndex) {
+    throw new RuntimeException("Not implemented here.");
+  }
+
   @Override
   public List<byte[]> wait(byte[][] objectIds, int timeoutMs, int numReturns) {
     return store.wait(objectIds, timeoutMs, numReturns);