Increase Pages E2E Test Coverage
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<summary>Context</summary>
Based on https://gitlab.com/groups/gitlab-com/gl-infra/-/epics/792#note_1116682375
> We have a single E2E Happy test of Pages currently that only runs on Staging. qa/specs/features/browser_ui/3_create/pages/new_static_page_spec.rb in the Gitlab repo - which is basically generating a Static Jekyll page and then verifying that external link loads properly.
>
> I'm currently working on enabling it on our test environments (package-and-qa & review-app) for us to be able to run that spec on every MR. Track issue here
>
> I'd be more than happy to discuss with anyone additional E2E testing routes we need and what testing strategy we need. Is there a person I should discuss this with?
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### Scenarios to be added
- [ ] private pages
- [ ] custom domains
- [ ] TLS support (self uploaded certificate)
- [ ] artifact browser
- [ ] fips (?)
- [ ] maybe also Let's encrypts support
issue