Smooth out CI build process for @next & latest /dist branch folders

[jessicamcinchak]

Spotting a couple bugs!

• latest is missing generated JSON Schema files: https://github.com/theopensystemslab/digital-planning-data-schemas/tree/dist/latest
• @next looks to be correctly updating examples/ & types/ but not the actual JSON Schema files: https://github.com/theopensystemslab/digital-planning-data-schemas/tree/dist/%40next
  • Also should manually delete digitalPlanningApplication.json since it's been renamed to application.json now