Add `someNE`

[Martoon-00]

Description

Motivation: some always returns a non-empty list, and it seems sane to reflect that in types.

I do not replace the original some because we cannot insert new Alternative typeclass into Functor - Applicative - Monad chain. And hiding the original some, as I think, isn't worth the potential confusion (when implementing Alternative instance and when just using some I would need different somes).

Related issues(s)

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[gromakovsky]

I am not sure why CI failed, but I see the following link in logs: https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/

I would try to update setup-haskell action first. Just add .4 here. It's a brainless way to fix it, maybe it will work. If it doesn't, we'll investigate further.

P. S. Also I think usually we don't merge the target branch into the PR branch in such cases :wink:

[Martoon-00]

Kaef, it helped