Fixes pytorch#107737 SGD doc blank line (pytorch#107738)

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Pull Request resolved: pytorch#107738
Approved by: https://github.com/mikaylagawarecki

torch/optim/sgd.py

@@ -92,8 +92,7 @@ def step(self, closure=None):
         return loss
 
 
-SGD.__doc__ = r"""\
-    Implements stochastic gradient descent (optionally with momentum).
+SGD.__doc__ = r"""Implements stochastic gradient descent (optionally with momentum).
 
     .. math::
        \begin{aligned}