Update build.yml

Author: stadub

.github/workflows/build.yml

@@ -20,8 +20,10 @@ jobs:
     name: Dotnet ${{ matrix.dotnet }} sample
     steps:
       - uses: actions/checkout@master
+      - uses: warrenbuckley/Setup-MSBuild@v1
       - name: Setup dotnet
         uses: actions/setup-dotnet@v1
         with:
+          # Folder location of where vswhere.exe is located if a self-hosted agent
           dotnet-version: ${{ matrix.dotnet }}
       - run: dotnet build TranslitModule