Revert System.Text.Encodings.Web

It breaks use inside of Roslyn

Author: AArnott

src/Microsoft.Windows.CsWin32/Microsoft.Windows.CsWin32.csproj

@@ -50,7 +50,6 @@
     <PackageReference Include="Nullable" Version="1.3.0" />
     <PackageReference Include="System.Memory" Version="4.5.4" PrivateAssets="none" />
     <PackageReference Include="System.Reflection.Metadata" Version="5.0.0" />
-    <PackageReference Include="System.Text.Encodings.Web" Version="4.7.2" />
     <PackageReference Include="System.Text.Json" Version="4.7.2" />
   </ItemGroup>