docs: Correct repository information (#11526)

Developer docs have been moved inside the getsentry/sentry-docs repo. Our docs pages should reflect this.

Author: szokeasaurusrex

develop-docs/development/docs/index.mdx

@@ -6,16 +6,11 @@ sidebar_order: 50
 
 Because documentation is a big part of what makes Sentry work we’ve outlined some guidelines about how this documentation is structured and how to extend it.
 
-Sentry's documentation lives in numerous repositories, so what we're covering here is _this site_ and our general approach to documentation. For a guide on contributing to user-facing docs, please see the `getsentry/sentry-docs` [contribution guidelines](https://docs.sentry.io/contributing/).
+This page primarily focuses on writing **developer-facing documentation**, although some concepts may also apply to user-facing documentation. We have separate [contribution guidelines](https://docs.sentry.io/contributing/) specifically for user-facing documenation.
 
-## Repositories
+## Repository
 
-Key places which contain documentation are:
-
-- [getsentry/sentry-docs](https://github.com/getsentry/sentry-docs) - [docs.sentry.io](https://docs.sentry.io/)
-- [getsentry/develop](https://github.com/getsentry/develop) - these docs!
-
-Our goal is to eventually unify the platform used for docs, which may result in us merging the above repositories.
+Sentry's documentation lives in the [getsentry/sentry-docs](https://github.com/getsentry/sentry-docs) repository. The developer documentation is located within the repository's [`develop-docs`](https://github.com/getsentry/sentry-docs/tree/master/develop-docs) directory.
 
 ## Stylistic Choices