Update docs/migration/fastapi.rst

Co-authored-by: Janek Nouvertné <provinzkraut@posteo.de>

docs/migration/fastapi.rst

@@ -265,7 +265,7 @@ The way dependencies parameters are passed differs between FastAPI and Litestar,
 
 Post json
 ~~~~~~~~~
-In FastAPI, you pass the JSON object directly as a parameter to the endpoint, you are forced to use pydantic. In Litestar, you use the `data` keyword argument and can pass whatever library supported.
+In FastAPI, you pass the JSON object directly as a parameter to the endpoint, which will then be validated by Pydantic. In Litestar, you use the `data` keyword argument. The data will be parsed and validated by the associated modelling library.
 
 .. tab-set::