Typo fix for docs repo links

doc/development/documentation/index.md

@@ -26,7 +26,7 @@ The source of the documentation exists within the codebase of each GitLab applic
 | --- | --- |
 | [GitLab](https://gitlab.com/gitlab-org/gitlab/) | [`/doc`](https://gitlab.com/gitlab-org/gitlab/tree/master/doc) |
 | [GitLab Runner](https://gitlab.com/gitlab-org/gitlab-runner/) | [`/docs`](https://gitlab.com/gitlab-org/gitlab-runner/tree/master/docs) |
-| [Omnibus GitLab](https://gitlab.com/gitlab-org/omnibus-gitlab/) | [`/doc`](https://gitlab.com/gitlab-org/gitlab/tree/master/doc) |
+| [Omnibus GitLab](https://gitlab.com/gitlab-org/omnibus-gitlab/) | [`/doc`](https://gitlab.com/gitlab-org/omnibus-gitlab/tree/master/doc) |
 | [Charts](https://gitlab.com/gitlab-org/charts/gitlab) | [`/doc`](https://gitlab.com/gitlab-org/charts/gitlab/tree/master/doc) |
 
 Documentation issues and merge requests are part of their respective repositories and all have the label `Documentation`.