graphbolt module missing

## 🐛 Bug

I installed the dgl package recently on my Windows laptop. I was not able to import the dgl.graphbolt module.

## To Reproduce
import dgl
empty_graph = dgl.graph (([],[]))
print(empty_graph)
import dgl.graphbolt as gb

## Error message

ModuleNotFoundError: No module named ‘dgl.graphbolt’

## Expected behavior

Expect to see the the details of the empty graph, just to see if my Python conda detected my dgl installation. It indeed has, since the print is successful. However, my script throws this error that the dgl.graphbolt module is not found.

## Environment
DGL Version: 2.0.0
Backend Library & Version: pytorch 2.0.0
OS: Windows
How you installed DGL (conda, pip, source): conda
Python version: 3.11.8
CUDA/cuDNN version: none

## Additional context

I tried the similar command above the first time with pytorch 2.2.0. However, I was told that DGL 2.0.0 and pytorch 2.2.0 aren't compatible, so I downgraded by pytorch to 2.0.0, and I still got the above error message.