fn backend copy stencil of tuple fails in nvcc

[tehrengruber]

GT4Py frontend code

@field_operator(backend=build_config.backend, grid_type=GridType.UNSTRUCTURED)
def _velocity_backup(
    u: Vec3VertexKField,
) -> Vec3VertexKField:
    return (
        u[0],
        u[1],
        u[2],
    )

def velocity_backup(config: Config, fields: StateContainer) -> None:
    _velocity_backup(
        u=fields.uvel,
        out=fields.uvel_bck,
        offset_provider=config.mesh.offset_provider,
    )

nvcc version tested: 12.5, 12.1

generated Gridtools C++:
__field_operator__velocity_backup_63e509ab74fa6b5b26de982401856de036ed55ba1c59e03010d298dcd9b3fbe6.zip