Update tbptt.rst

Author: kilavvy

docs/source-pytorch/common/tbptt.rst

@@ -2,7 +2,7 @@
 Truncated Backpropagation Through Time (TBPTT)
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-Truncated Backpropagation Through Time (TBPTT) performs backpropogation every k steps of
+Truncated Backpropagation Through Time (TBPTT) performs backpropagation every k steps of
 a much longer sequence. This is made possible by passing training batches
 split along the time-dimensions into splits of size k to the
 ``training_step``. In order to keep the same forward propagation behavior, all