docs: remove Ineffective code block (backport #20703) (#20711)

Author: mergify[bot]

docs/docs/learn/advanced/05-encoding.md

@@ -49,8 +49,6 @@ for their types, this is autogenerated via [buf](https://buf.build/)
 
 If modules use [Collections](../../build/packages/02-collections.md) or [ORM](../../build/packages/03-orm.md), encoding and decoding are handled, marshal and unmarshal should not be handled manually unless for specific cases identified by the developer.
 
-```go reference
-
 ### Gogoproto
 
 Modules are encouraged to utilize Protobuf encoding for their respective types. In the Cosmos SDK, we use the [Gogoproto](https://github.com/cosmos/gogoproto) specific implementation of the Protobuf spec that offers speed and DX improvements compared to the official [Google protobuf implementation](https://github.com/protocolbuffers/protobuf).