Don't build msys2

Author: tjammer

.github/workflows/main.yml

@@ -17,7 +17,6 @@ jobs:
           - windows-latest
         windows_env:
           - cygwin
-          - msys2
     runs-on: ${{ matrix.os }}
     steps:
       - run: git config --global core.autocrlf false
@@ -40,13 +39,6 @@ jobs:
             D:\opamroot
           key: ${{ runner.os }}-${{ matrix.windows_env }}-opam-${{ hashFiles('install.ps1') }}
 
-      - name: Add MSys2 to PATH and install prerequisites
-        if: matrix.windows_env == 'msys2'
-        run: |
-          "C:\msys64" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
-          C:\msys64\usr\bin\pacman.exe --noconfirm -Syuu  # Core update (in case any core packages are outdated)
-          C:\msys64\usr\bin\pacman.exe --noconfirm -Syuu m4 make mingw-w64-i686-gcc mingw-w64-x86_64-gcc rsync unzip
-
       - name: Install opam
         if: steps.cache-opam.outputs.cache-hit != 'true'
         run: |
@@ -59,7 +51,7 @@ jobs:
 
       - name: Init opam
         if: steps.cache-opam.outputs.cache-hit != 'true'
-        run: opam init --yes --no-setup ${{ matrix.windows_env == 'msys2' && '--cygwin-local-install' || '' }}
+        run: opam init --yes --no-setup
 
       - name: Restrict testing to available compilers
         if: steps.cache-opam.outputs.cache-hit != 'true'