WIP: Group SAML Demo Package

What does this MR do?

Provides us with pipelines to build omnibus packages for installing GitLab with Group level SAML

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Documentation created/updated
• Has been reviewed by UX
• Internationalization required/considered
• If paid feature, have we considered GitLab.com plan and how it works for groups and is there a design for promoting it to users who aren't on the correct plan
• End-to-end tests pass (package-qa manual pipeline job)

What are the relevant issue numbers?

&40 (closed)