v3.12.0-beta.1: ⚠️ Set `SESSION_COOKIE_SECURE = True`, Fix UI Demo

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Unable to build. Use https://github.com/TACC/Core-CMS/releases/tag/v3.12.0-beta.2 instead.

Warning
The UI demo is not successfully fixed by #692.

Fixed

• fix: serve ui demo if it exists (#692)
• hotfix: set SESSION_COOKIE_SECURE = True (#695)
• docs: fix broken link (customize admin ui text) (#694)

Changed

• feat: do not let news editors add plain images (#691)
• chore(taccsite_custom): delete migrated cms's (#690)
• enhance: improve admin UI permissions error text (#693)