In the implementation of forward gradient, use ones for the value of the dummy variable to insulate ourselves from the changes in TF core concerning the gradient of the division operator.
In the implementation of forward gradient, use ones for the value of the dummy variable to insulate ourselves from the changes in TF core concerning the gradient of the division operator.

PiperOrigin-RevId: 301171083

google/tf-quant-finance,google/tf-quant-finance