fix: invalid payload.collections type

[r1tsuu]

What?

payload.collections was improperly typed.
This doesn't seem to work: (the type is {})

collections: {
  [slug: CollectionSlug]: Collection
} = {}

However, this does:

collections: Record<CollectionSlug, Collection> = {}

Additionally, the same fix applied to Permissions, PolymorphicUploadField['admin']['sortOptions'], PolymorphicRelationshipField['admin']['sortOptions']

[github-actions]

🚀 This is included in version v3.1.0