Minor tweaks to readme and legacy dependency

Author: kzu

src/Attributed/Attributed.msbuildproj

@@ -7,6 +7,6 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="NuGetizer" Version="1.2.4" />
-    <PackageReference Include="Devlooped.Extensions.DependencyInjection" Version="2.1.0" />
+    <PackageReference Include="Devlooped.Extensions.DependencyInjection" Version="2.2.1" />
   </ItemGroup>
 </Project>