Enable timestep shifting (#13)

- Enable timestep shifting (c72c25b9d93a9a9cbc111d6401102925fc3c0cc3)


Co-authored-by: - <[email protected]>

scheduler/scheduler_config.json

@@ -7,7 +7,7 @@
   "max_image_seq_len": 4096,
   "max_shift": 1.15,
   "num_train_timesteps": 1000,
-  "shift": 1.0,
+  "shift": 3.0,
   "shift_terminal": null,
   "stochastic_sampling": false,
   "time_shift_type": "exponential",