Add back net9.0

Author: paulirwin

src/dotnet/tools/Lucene.Net.Tests.Cli/Lucene.Net.Tests.Cli.csproj

@@ -25,7 +25,7 @@
 
   <PropertyGroup>
     <!-- Allow specific target framework to flow in from TestTargetFrameworks.props -->
-    <TargetFrameworks Condition=" '$(TargetFramework)' == '' ">net10.0;net8.0</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(TargetFramework)' == '' ">net10.0;net9.0;net8.0</TargetFrameworks>
     <AssemblyTitle>Lucene.Net.Tests.Cli</AssemblyTitle>
   </PropertyGroup>
 

src/dotnet/tools/lucene-cli/lucene-cli.csproj

@@ -24,7 +24,7 @@
   <Import Project="$(SolutionDir).build/nuget.props" />
 
   <PropertyGroup>
-    <TargetFrameworks>net10.0;net8.0</TargetFrameworks>
+    <TargetFrameworks>net10.0;net9.0;net8.0</TargetFrameworks>
     <RollForward>Major</RollForward>
 
     <IsPublishable>true</IsPublishable>