Use .NET 8 SDK in release pipeline

Author: johnkors

.github/workflows/Release.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Setup .NET
         uses: actions/setup-dotnet@v3
         with:
-          dotnet-version: 6.0.x
+          dotnet-version: 8.0.x
       - run: echo "ACTIONS_ALLOW_UNSECURE_COMMANDS=true" >> $GITHUB_ENV
       - name: Install GitVersion
         uses: gittools/actions/gitversion/setup@v0