Bump to .NET 9

Author: ds5678

.github/workflows/build.yml

@@ -16,7 +16,7 @@ jobs:
     - name: Setup .NET
       uses: actions/setup-dotnet@v4.3.1
       with:
-        dotnet-version: 8.0.x
+        dotnet-version: 9.0.x
     - name: Restore dependencies
       run: dotnet restore
     - name: Build

Directory.Build.props

@@ -1,6 +1,6 @@
 <Project>
 	<PropertyGroup>
-		<TargetFramework>net8.0</TargetFramework>
+		<TargetFramework>net9.0</TargetFramework>
 		<LangVersion>Latest</LangVersion>
 		<Nullable>enable</Nullable>
 		<IsAotCompatible>true</IsAotCompatible>