Update desktop-build.yml

Author: maSchoeller

.github/workflows/desktop-build.yml

@@ -19,7 +19,7 @@ jobs:
     # Authenticates packages to push to GPR
     - uses: actions/setup-dotnet@v1
       with:
-        dotnet-version: '3.1.100' # SDK Version to use.
+        dotnet-version: '5.0.202' # SDK Version to use.
     - name: Build Project
       run: |
         cd src/Desktop/MaSchoeller.Extensions.Desktop/