fix(#2440): view.width.padding may be a number or function returning a number

[reyniersbram]

Update accepted types for view.width option so padding can be set. See #2440.
Overrides documentation change of #2441

[Akmadan23]

Good job! This actually fixes the issue raised by @IZ-ZI.
By the way @alex-courtis I took a brief look to nvim-tree/view.lua and having padding as string or function actually results in 0 padding, so probably it's better to only accept numbers.

Edit: I missed the get_size function and your comment, so yes, now we just have to specify in the documentation that the function should return a number.

[alex-courtis]

By the way @alex-courtis I took a brief look to nvim-tree/view.lua and having padding as string

Yes. It's good to see the type validator working and protecting against this ;)

[alex-courtis]

Many thanks for your contribution!

[alex-courtis]

specify in the documentation that the function should return a number.

Done