add 9.0.x to yml and test setup

Author: mgravell

.github/workflows/dotnet-integration.yml

@@ -22,7 +22,8 @@ jobs:
         with:
           dotnet-version: |
             6.0.x
-            8.0.x 
+            8.0.x
+            9.0.x
 
       - name: Build
         run: dotnet build Dapper.AOT.sln -c Debug

.github/workflows/dotnet.yml

@@ -23,6 +23,7 @@ jobs:
           dotnet-version: |
             6.0.x
             8.0.x
+            9.0.x
 
       - uses: dotnet/nbgv@master
         with:

test/Dapper.AOT.Test/Verifiers/Verifier.cs

@@ -78,6 +78,10 @@ internal Task ExecuteAsync(AnalyzerTest<XUnitVerifier> test, string source,
         }
 #if NETFRAMEWORK
         test.ReferenceAssemblies = ReferenceAssemblies.NetFramework.Net472.Default;
+#elif NET9_0_OR_GREATER
+        test.ReferenceAssemblies = new ReferenceAssemblies("net9.0",
+            new PackageIdentity("Microsoft.NETCore.App.Ref", "9.0.0"),
+            Path.Combine("ref", "net9.0"));
 #elif NET8_0_OR_GREATER
         test.ReferenceAssemblies = new ReferenceAssemblies("net8.0",
             new PackageIdentity("Microsoft.NETCore.App.Ref", "8.0.0"),