Stop targeting .NET 6 and .NET 7

Author: mauroservienti

src/ServiceComposer.AspNetCore.Testing/ServiceComposer.AspNetCore.Testing.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>net6.0;net7.0;net8.0;net9.0;net10.0</TargetFrameworks>
+        <TargetFrameworks>net8.0;net9.0;net10.0</TargetFrameworks>
     </PropertyGroup>
 
     <PropertyGroup>
@@ -28,16 +28,6 @@
         <FrameworkReference Include="Microsoft.AspNetCore.App" />
     </ItemGroup>
 
-    <ItemGroup Condition="'$(TargetFramework)' == 'net6.0'">
-        <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="[6.0.12, 7.0.0)" />
-        <PackageReference Include="System.Text.Json" Version="[6.0.11, 7.0.0)" Label="Dependencies not directly used but required to address security vulnerabilities" />
-    </ItemGroup>
-
-    <ItemGroup Condition="'$(TargetFramework)' == 'net7.0'">
-        <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="[7.0.1, 8.0.0)" />
-        <PackageReference Include="System.Text.Json" Version="[8.0.5, 9.0.0)" Label="Dependencies not directly used but required to address security vulnerabilities" />
-    </ItemGroup>
-
     <ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
         <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="[8.0.0, 9.0.0)" />
         <PackageReference Include="System.Text.Json" Version="[8.0.5, 9.0.0)" Label="Dependencies not directly used but required to address security vulnerabilities" />