defineZYP

### Overview Add module autogl.module.train.ssl, which will contains many trainers to do self-supervised task. Now, it only have one trainer using GraphCL and do the semi-supervised downstream tasks. And a...

**Describe the bug** When running /autogl/test/nas/node_classification.py with AUTOGL_BACKEND=dgl, I got the following error. ``` Traceback (most recent call last): File "node_classification.py", line 116, in model = algo.search(space, dataset, esti) File...