add .net8 to target frameworks

Author: dawkaka

apitoolkit-dotnet.csproj

@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
-
   <PropertyGroup>
-    <Version>1.0.7</Version>
-    <TargetFramework>net6.0</TargetFramework>
+    <Version>1.0.8</Version>
+    <TargetFrameworks>net6.0;net7.0;net8.0</TargetFrameworks>
     <PackageId>ApiToolkit.Net</PackageId>
     <Authors>ApiToolkit</Authors>
     <Company>ApiToolkit</Company>
@@ -26,12 +25,11 @@
     <PackageReference Include="Microsoft.AspNetCore.Http.Extensions" Version="2.2.0" />
     <PackageReference Include="Microsoft.AspNetCore.Routing" Version="2.2.2" />
     <PackageReference Include="Microsoft.AspNetCore.TestHost" Version="6.0.0" />
-    <PackageReference Include="Microsoft.AspNetCore.App" />
+    <FrameworkReference Include="Microsoft.AspNetCore.App" />
     <!-- Deprecated -->
     <PackageReference Include="Microsoft.AspNetCore.Hosting" Version="2.2.7" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.6.2" />
     <PackageReference Include="NUnit" Version="3.13.3" />
   </ItemGroup>
-
 </Project>