Update dotnet-build.yml to fix push nuget by release-main

Author: VladislavAntonyuk

.github/workflows/dotnet-build.yml

@@ -355,7 +355,7 @@ jobs:
 
       -  name: Upload artifact
          if: github.event_name != 'pull_request'
-         run: |
+         run: >
            dotnet nuget push
            **/*.nupkg
            --source "https://nuget.pkg.github.com/CommunityToolkit/index.json"