[Bug fix] Using loaded checkpoint with --do_predict (instead of… (#3437)

* Using loaded checkpoint with --do_predict

Without this fix, I'm getting near-random validation performance for a trained model, and the validation performance differs per validation run. I think this happens since the `model` variable isn't set with the loaded checkpoint, so I'm using a randomly initialized model. Looking at the model activations, they differ each time I run evaluation (but they don't with this fix).

* Update checkpoint loading

* Fixing model loading

examples/glue/run_pl_glue.py

@@ -192,5 +192,5 @@ if __name__ == "__main__":
     # Optionally, predict on dev set and write to output_dir
     if args.do_predict:
         checkpoints = list(sorted(glob.glob(os.path.join(args.output_dir, "checkpointepoch=*.ckpt"), recursive=True)))
-        GLUETransformer.load_from_checkpoint(checkpoints[-1])
+        model = model.load_from_checkpoint(checkpoints[-1])
         trainer.test(model)

examples/ner/run_pl_ner.py

@@ -192,5 +192,5 @@ if __name__ == "__main__":
         # https://github.com/PyTorchLightning/pytorch-lightning/blob/master\
         # /pytorch_lightning/callbacks/model_checkpoint.py#L169
         checkpoints = list(sorted(glob.glob(os.path.join(args.output_dir, "checkpointepoch=*.ckpt"), recursive=True)))
-        NERTransformer.load_from_checkpoint(checkpoints[-1])
+        model = model.load_from_checkpoint(checkpoints[-1])
         trainer.test(model)