github: Use GitHub's Choco-Install function to retry installs

Apparently, two instances of "choco install mingw" running simultaneously
(for go-version 1.18.x and 1.19.x) would often cause at least one of them
to fail to connect to SourceForge:

    ERROR: The remote file either doesn't exist, is unauthorized,
    or is forbidden for url
    'https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Personal%20Builds/ray_linn/GCC-10.X-with-ada/GCC-10.2.0-crt-8.0.0-with-ada-20201019.7z/download'.
    Exception calling "GetResponse" with "0" argument(s):
    "The request was aborted: Could not create SSL/TLS secure channel."

With Choco-Install however, it simply works every single time!

Thanks to keymanapp/api.keyman.com#156 for the great tip!

See the definition of the PowerShell Choco-Install function here:
https://github.com/actions/runner-images/blob/main/images/win/scripts/ImageHelpers/ChocoHelpers.ps1

.github/workflows/test.yml

@@ -49,9 +49,11 @@ jobs:
         brew install pandoc
     - if: matrix.os == 'windows-latest'
       run: |
-        choco install pandoc
-        choco install mingw --version 10.2.0 --allow-downgrade
+        Choco-Install -PackageName pandoc
     - run: pandoc -v
+    - if: matrix.os == 'windows-latest'
+      run: |
+        Choco-Install -PackageName mingw -ArgumentList "--version","10.2.0","--allow-downgrade"
     - if: matrix.os == 'ubuntu-latest'
       name: Install dart-sass-embedded Linux
       run: |