Always return a tuple for instance of DPNPUnaryTwoOutputsFunc class

Author: antonwolfy

dpnp/dpnp_algo/dpnp_elementwise_common.py

@@ -428,7 +428,7 @@ def __call__(
             if not isinstance(res, dpnp_array):
                 # Always return dpnp.ndarray
                 out[i] = dpnp_array._create_from_usm_ndarray(res)
-        return out
+        return tuple(out)
 
 
 class DPNPBinaryFunc(BinaryElementwiseFunc):