try to enable dotnet 8 on appveyor, and enable roll forward in global.json

Author: smoothdeveloper

appveyor.yml

@@ -2,6 +2,9 @@ init:
   - git config --global core.autocrlf input
   - net start MSSQL$SQL2019
 image: Visual Studio 2022
+before_build:
+# switch on dotnet 8 on appveyor: https://github.com/appveyor/ci/issues/3897#issuecomment-1827682384
+- choco install dotnet-sdk --version 8.0.100
 build_script:
   - cmd: build.cmd GenerateDocs
 test: off

global.json

@@ -1 +1,7 @@
-{ "sdk": { "version": "8.0.100" } }
+{
+  "sdk": 
+  {
+    "version": "8.0.100"
+    , "rollForward": "latestFeature"
+  }
+}