GRU: Fix a typo in doc comment about reset_after.
`reset_after` is a named argument, not string.
@@ -231,7 +231,7 @@ class GRU(recurrent.DropoutRNNCellMixin, recurrent.GRU):
The second variant is compatible with CuDNNGRU (GPU-only) and allows
inference on CPU. Thus it has separate biases for `kernel` and
- `recurrent_kernel`. To use this variant, set `'reset_after'=True` and
+ `recurrent_kernel`. To use this variant, set `reset_after=True` and
`recurrent_activation='sigmoid'`.
For example:
