Docs: Remove include.user from RequestData integration (#14127)

## DESCRIBE YOUR PR

In 9.x,
[`RequestDataIncludeOptions`](https://github.com/getsentry/sentry-javascript/blob/c37d4e5a7546be97afa92ae5d7950cc7b6542cdd/packages/core/src/integrations/requestdata.ts#L8-L15)
no longer has `user`. Presumably because of this change from the
migration guide:

> The `requestDataIntegration` will no longer automatically set the user
from `request.user` when `express` is used. Starting in v9, you'll need
to manually call `Sentry.setUser()` e.g. in a middleware to set the user
on Sentry events.

However the option is still listed here:
https://docs.sentry.io/platforms/javascript/guides/nextjs/configuration/integrations/requestdata/

This PR updates the docs to match the new types.

## IS YOUR CHANGE URGENT?  

- [x] None: Not urgent, can wait up to 1 week+

## SLA

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- Please give the docs team up to 1 week to review your PR unless you've
added an urgent due date to it.
Thanks in advance for your help!

## PRE-MERGE CHECKLIST

*Make sure you've checked the following before merging your changes:*

- [ ] Checked Vercel preview for correctness, including links
- [ ] PR was reviewed and approved by any necessary SMEs (subject matter
experts)
- [ ] PR was reviewed and approved by a member of the [Sentry docs
team](https://github.com/orgs/getsentry/teams/docs)

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gonna need some rights from me in order to utilize my contributions in
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Author: camjackson

includes/platforms/configuration/integrations/requestdata.mdx

@@ -20,11 +20,6 @@ Controls what types of data are added to the event:
   ip: boolean  // default: false,
   query_string: boolean  // default: true,
   url: boolean  // default: true,
-  user: boolean | {
-    id: boolean  // default: true,
-    username: boolean  // default: true,
-    email: boolean  // default: true,
-  },
 }
 ```