Important change in Docs in Utf8Json (restsharp#1600)

All other includes of properties or other imp things are with grey background but here in this case Utf8Json wasn't there with grey background. It's a minor change but as a reader anyone can figure it out the difference. I hope you will consider this change as it is small but an important Visual change.

Author: ShardulTiurwadkar

docs/usage/serialization.md

@@ -77,7 +77,7 @@ If you need to use different settings, you can supply your instance of
 
 ## Utf8Json
 
-The 'Utf8Json' package is known to be the fastest JSON serializer for .NET.
+The `Utf8Json` package is known to be the fastest JSON serializer for .NET.
 
 RestSharp supports `Utf8Json` serializer via a separate package. You can install it
 from NuGet: