fix target framework tips

Author: walterlv

src/DotNetCampus.CommandLine/DotNetCampus.CommandLine.csproj

@@ -4,8 +4,8 @@
     <!--
       We add net8.0 to support collection expressions for Immutables.
       We add net6.0 to support ArgumentNullException.ThrowIfNull().
-      We add net5.0 to support OperatingSystem.IsWindows()/IsLinux()/IsMacOS() and nint.Parse().
-      We add netcoreapp3.1 to support basic string methods.
+      We add net5.0 to support OperatingSystem.IsWindows()/IsLinux()/IsMacOS().
+      We add netcoreapp3.1 to support basic string methods and ValueTask.
     -->
     <TargetFrameworks>net8.0;net6.0;net5.0;netcoreapp3.1;netstandard2.0</TargetFrameworks>
     <ImplicitUsings>enable</ImplicitUsings>