docs(graphql): use latest mercurius package

Author: Paulo Eduardo Rezende

content/graphql/quick-start.md

@@ -16,7 +16,7 @@ $ npm i @nestjs/graphql @nestjs/apollo graphql apollo-server-express
 # npm i @nestjs/graphql @nestjs/apollo graphql apollo-server-fastify
 
 # For Fastify and Mercurius
-# npm i @nestjs/graphql @nestjs/mercurius graphql mercurius@^9
+# npm i @nestjs/graphql @nestjs/mercurius graphql mercurius
 ```
 
 > warning **Warning** `@nestjs/graphql@>=9` and `@nestjs/apollo^10` packages are compatible with **Apollo v3** (check out Apollo Server 3 [migration guide](https://www.apollographql.com/docs/apollo-server/migration/) for more details), while `@nestjs/graphql@^8` only supports **Apollo v2** (e.g., `[email protected]` package).