ci: add dotnet pack and use Release

Author: guitarrapc

.github/workflows/build-debug.yaml

@@ -18,5 +18,6 @@ jobs:
     steps:
       - uses: Cysharp/Actions/.github/actions/checkout@main
       - uses: Cysharp/Actions/.github/actions/setup-dotnet@main
-      - run: dotnet build -c Debug
-      - run: dotnet test -c Debug --no-build
+      - run: dotnet build -c Release
+      - run: dotnet test -c Release --no-build
+      - run: dotnet pack -c Release --no-build -p:IncludeSymbols=true -p:SymbolPackageFormat=snupkg -o $GITHUB_WORKSPACE/artifacts