Hotfix shape arg

[yasahi-hpc]

This PR aims at fixing the behavior of APIs with optional shape arguments.
Following modifications are made:

1. Fix the function to compute a new shape to work on the specified axis (KokkosFFT_padding.hpp)
2. Update tests accordingly (Test_Padding.cpp)
3. Behaviors in FFT APIs with shape args are fixed (KokkosFFT_Transform.hpp)
4. Update tests accordingly (Test_Transform.cpp)

In detail, shape argument n or s should work on the specified axis.
For example, shapes would change in the following manner.

# 2D FFT on 2D View
x = np.random.rand(4, 3) + 1j * np.random.rand() # shape (4, 3) 
x_hat = np.fft.irfft2(x, axes=(-1, -2)) # shape (6, 3)
x_hat = np.fft.irfft2(x, axes=(-1, -2), s=(4, 3)) # shape (3, 4)
x_hat = np.fft.irfft2(x, axes=(-1, -2), s=(6, 3)) # shape (3, 6)
x_hat = np.fft.irfft2(x, axes=(-1, -2), s=(6, 5)) # shape (5, 6)

Although this functionality may be not that useful,
it can be reused to accept Views with LayoutStrided