Correct typo

Correct typo in A GENTLE INTRODUCTION TO TORCH.AUTOGRAD

Author: hafezgh

beginner_source/blitz/autograd_tutorial.py

@@ -40,7 +40,7 @@
 shape (1,1000).
 
 .. note::
-    This tutorial work only on CPU and will not work on GPU (even if tensor are moved to CUDA).
+    This tutorial work only on CPU and will not work on GPU (even if tensors are moved to CUDA).
 
 """
 import torch