Create test classes for MNodeResourceHandler and CNodeResourceHanlder

[taojing2002]

We don't have test classes for the MNodeResourceHandler and CNodeResourceHanlder classes. Matthew and I think it is a good idea to write them. And Mockito is good candidate to handle this situation. Here is some code we can borrow.

Since we have so many rest commands needed to be tested, we will gradually add them. The start the point will be the new ones of reindex and updateIdMetadata.

[taojing2002]

Matthew wrote some example here:

try (MockedStatic<MNodeService> ignored = Mockito.mockStatic(MNodeService.class)) {
            MNodeService mockMNodeService = Mockito.mock(MNodeService.class);
            Mockito.when(MNodeService.getInstance()).thenReturn(mockMNodeService);
            Mockito.when(mockMNodeService).reindex(any(), any()).thenReturn(Boolean.TRUE);

            // Verify that reindex() was called
            Mockito.verify(mockMNodeService, Mockito.times(1)).reindex(any(), any());
        }