Function shrink_forward 

pub fn shrink_forward<T: Triton, const BLOCK_SIZE: i32>(
    x_ptr: T::Pointer<f32>,
    y_ptr: T::Pointer<f32>,
    n_elements: i32,
    lambd: f32,
    bias: f32,
)
where
    T::I32Tensor: Tensor<i32, 1> + Comparison<i32, BoolTensor = T::BoolTensor>,
    T::Pointer<f32>: AddOffsets<i32, 1, T::I32Tensor, Output = T::Tensor<T::Pointer<f32>>>,

Forward: y = x - bias if x > lambd, x + bias if x < -lambd, else 0