Fix "noindex" documentation and usage

doc/development/documentation/metadata.md

@@ -92,7 +92,7 @@ When this metadata is set on a page:
 The following metadata is optional and is not actively maintained.
 
 - `feedback`: Set to `false` to not include the "Help & Feedback" footer.
-- `noindex`: Set to `false` to prevent the page from being indexed by search engines.
+- `noindex`: Set to `true` to prevent the page from being indexed by search engines.
 - `redirect_to`: Used to control redirects. For more information, see [Redirects in GitLab documentation](redirects.md).
 - `searchbar`: Set to `false` to not include the search bar in the page header.
 - `toc`: Set to `false` to not include the "On this page" navigation.

doc/update/breaking_window.md

@@ -2,7 +2,7 @@
 stage: none
 group: none
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://handbook.gitlab.com/handbook/product/ux/technical-writing/#assignments
-noindex: false
+noindex: true
 ---
 
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