Setup .NET Core on all platforms

Setup .NET Core on both windows and linux platforms.

Author: lahirumaramba

.github/workflows/ci.yml

@@ -19,7 +19,6 @@ jobs:
       uses: actions/checkout@v1
 
     - name: Setup .NET Core
-      if: matrix.os == 'ubuntu-latest'
       uses: actions/setup-dotnet@v1
       with:
         dotnet-version: 2.2.108