adding a workflow for CI

Signed-off-by: Lev Nachmanson <[email protected]>

Author: levnach

.github/workflows/build.yml

@@ -14,6 +14,10 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@master
+
+      - name: Add msbuild to PATH
+        uses: microsoft/[email protected]
+
       - name: Restore NuGet Packages
         run: nuget restore GraphLayout/GraphLayout.sln