better handle distortion coef

[anhtu293]

• New feature 1 : Better handle distortion coef for equidistant projection: both float and list are accepted.

# Python code snippet showing how to use it.
import torch
from aloscene import Depth

x = torch.rand(size=(1, 1, 20, 20))
depth1 = Depth(x, projection="equidistant", distortion=[0.5])
depth2 = Depth(x, projection="equidistant", distortion=0.5)

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This pull request includes

• Bug fix (non-breaking change which fixes an issue)
• [x ] New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

[anhtu293]

@tflahaul