[ci] Prevent Python downgrading to pypy on Windows (2) (#5198)
[ci] Prevent Python downgrading to pypy on Windows (2) (#5198)

* Update test_windows.ps1

* Update .appveyor.yml

* Update test_windows.ps1

* Update test_windows.ps1

* Update test_windows.ps1

* Update test_windows.ps1

* Update test_windows.ps1

* Update .appveyor.yml
henry0312/LightGBM,microsoft/LightGBM,microsoft/LightGBM,microsoft/LightGBM,henry0312/LightGBM,henry0312/LightGBM,microsoft/LightGBM,henry0312/LightGBM,microsoft/LightGBM,henry0312/LightGBM