LightGBM

[ci] Add debian-clang-devel CI job for the R package (#4164)

* [ci] Add debian-clang-devel CI job for the R package

* [ci] Add debian-clang-devel CI job for the R package

* fixes

* fix test

* update cran-comments

* re-trigger CI

* catch warnings and notes

* fail with only a NOTE

* uncomment CI code

* remove env vars in windows tests

* Update R-package/cran-comments.md

Co-authored-by: Nikita Titov <nekit94-08@mail.ru>

Co-authored-by: StrikerRUS <nekit94-12@hotmail.com>
Co-authored-by: Nikita Titov <nekit94-08@mail.ru>