[R-package][ci] update to R 4.0.2 for Windows CI jobs (fixes #3191) (#3193)
[R-package][ci] update to R 4.0.2 for Windows CI jobs (fixes #3191) (#3193)

* first attempt

* update to R 4.0.2

* no duplicate builds

* [R-package] [ci] update to R 4.0.2 for Windows CI jobs (fixes #3191)
microsoft/LightGBM,henry0312/LightGBM,henry0312/LightGBM,microsoft/LightGBM,microsoft/LightGBM,henry0312/LightGBM,microsoft/LightGBM,henry0312/LightGBM,henry0312/LightGBM,microsoft/LightGBM