Incorrect return type for _pad_projections_to_second_power() function

[yousefmoazzam]

The return type currently says that either a cp.ndarray or a tuple can be returned:

httomolibgpu/httomolibgpu/prep/phase.py

Line 350 in ce1c15f

def _pad_projections_to_second_power(tomo: cp.ndarray) -> Union[cp.ndarray, tuple]:

But, the function actually returns a tuple containing two elements: a cp.ndarray and a tuple:

httomolibgpu/httomolibgpu/prep/phase.py

Lines 360 to 363 in ce1c15f

	Returns
	-------
	ndarray: padded 3d projection data
	tuple: a tuple with padding dimensions

httomolibgpu/httomolibgpu/prep/phase.py

Line 386 in ce1c15f

return padded_tomo, pad_tup

where the second element in the "outer tuple" is a tuple containing two int values I think?

Therefore, I think the correct return type is Tuple[cp.ndarray, Tuple[int, int]].