docs(rtk-query): Clarify standard slice exports

The existing documentation implies that standard slices *only* export
action creators and reducers. This can create confusion when users
compare this with fuller implementations within the codebase, such as
the `postsSlice.ts` example shown earlier in Part 6.

That file demonstrates that robust slices require exporting additional
items like async thunks, types, selectors, and listener middleware.

This change updates the wording to clarify that the original statement
refers to the *minimal* exports needed from `createSlice`, providing
better and unambiguous context before contrasting with `createApi`
exports.

Author: BonaventureCJ

docs/tutorials/essentials/part-7-rtk-query-basics.md

@@ -216,7 +216,7 @@ For TypeScript usage, **the `builder.query()` and `builder.mutation()` endpoint
 
 #### Exporting API Slices and Hooks
 
-In our earlier slice files, we just exported the action creators and the slice reducers, because those are all that's needed in other files. With RTK Query, we typically export the entire "API slice" object itself, because it has several fields that may be useful.
+From our earlier `createSlice` functions, we only needed to export just the action creators and the slice reducers, because those are the only part of the slice functions that are needed in other files. With RTK Query, we typically export the entire "API slice" object itself, because it has several fields that may be useful.
 
 Finally, look carefully at the last line of this file. Where's this `useGetPostsQuery` value coming from?