Staging-28

What's Changed

• Issue 1143 - banner update by @dave-kennedy-ecs in #1255
• Fix requirements.txt breaking connection pool by @zandercymatics in #1297
• Production release cadence ADR by @abroddrick in #1254
• Added bug handling/ triaging readme by @abroddrick in #1280
• Updated domain invitation text content by @abroddrick in #1293
• Ticket #1194: Disable New Requests by @zandercymatics in #1256
• Hotfix - Fix broken IS_PRODUCTION setting by @zandercymatics in #1303
• Issue #476: Adding CORS headers for cloud.gov site pages by @therealslimhsiehdy in #1299

Full Changelog: staging-27...staging-28