Hide `Pages` in settings panle

What does this MR do and why?

Hide Pages row in settings panel if disable public access in saas
Relates to: https://jihulab.com/gitlab-cn/gitlab/-/issues/1222#note_2272967

Screenshots or screen recordings

before	after

How to set up and validate locally

1. install pages by

gdk install gitlab-pages

1. enable pages
2. enable access control
3. disable public access
4. simulate saas
5. create a project and click Settings > General > Visibility, project features, permissions and search Pages

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.