Crash when calling Tensor::nonzero() on a tensor that all values are zero.

[KhaledHosseini]

Describe the bug

Crash when calling Tensor::nonzero() on a tensor that all values are zero. Is this a bug or is the behavior intentional? (because of zero size tensor).
To Reproduce

use burn::{
    backend::wgpu::Wgpu,
    tensor::{backend::Backend, Tensor},
};

type MyBackend= Wgpu;

fn main() {
   let device = Default::default();
   let bools = Tensor::<MyBackend, 1>::zeros([1000], &device).bool();
   // let bools = Tensor::<MyBackend, 1>::full([1000],0.0, &device).bool();
    let non_zero_indices = Tensor::nonzero(bools); // panics ... we need to use Tensor::any() before calling this function.
}

Expected behavior
Should return a vector of zero size tensors or a vector of Option.