feat: update references to net8 (#421)

Update the used references from Microsoft to `8.0.0` and use .NET 8 in
the Examples solution.

---------

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Directory.Packages.props

@@ -6,7 +6,7 @@
 
 	<ItemGroup>
 		<PackageVersion Include="System.Linq.Async" Version="6.0.1" />
-		<PackageVersion Include="System.Threading.Channels" Version="7.0.0" />
+		<PackageVersion Include="System.Threading.Channels" Version="8.0.0" />
 		<PackageVersion Include="TestableIO.System.IO.Abstractions" Version="19.2.69" />
 		<PackageVersion Include="System.IO.Compression" Version="4.3.0" />
 		<PackageVersion Include="System.IO.FileSystem.AccessControl" Version="5.0.0" />
@@ -20,7 +20,7 @@
 	<ItemGroup>
 		<PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.7.0" />
 		<PackageVersion Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.4" />
-		<PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="7.0.0" />
+		<PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="8.0.0" />
 	</ItemGroup>
 
 	<ItemGroup>

Examples/Directory.Build.props

@@ -4,7 +4,7 @@
 	        Condition="Exists('$(MSBuildThisFileDirectory)/../Directory.Build.props')" />
 
 	<PropertyGroup>
-		<TargetFramework>net7.0</TargetFramework>
+		<TargetFramework>net8.0</TargetFramework>
 		<LangVersion>latest</LangVersion>
 		<ImplicitUsings>disable</ImplicitUsings>
 		<Nullable>enable</Nullable>