[Doc] Fix package name in __Schema section (#6053)

Author: BoD

docs/source/migration/4.0.mdx

@@ -574,7 +574,7 @@ When using the `generateSchema` option, to avoid a name clash with the introspec
 import com.example.type.__Schema
 
 // With
-import data.builders.schema.__Schema
+import com.example.schema.__Schema
 ```
 
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