re-fix example playgrounds

Author: mattpolzin

JSONAPI.playground/Pages/Full Client & Server Example.xcplaygroundpage/Contents.swift

@@ -30,7 +30,7 @@ typealias UnidentifiedJSONEntity<Description: ResourceObjectDescription> = JSONA
 // Create relationship typealiases because we do not expect
 // JSON:API Relationships for this particular API to have
 // Metadata or Links associated with them.
-typealias ToOneRelationship<Entity: Identifiable> = JSONAPI.ToOneRelationship<Entity, NoMetadata, NoLinks>
+typealias ToOneRelationship<Entity: JSONAPIIdentifiable> = JSONAPI.ToOneRelationship<Entity, NoMetadata, NoLinks>
 typealias ToManyRelationship<Entity: Relatable> = JSONAPI.ToManyRelationship<Entity, NoMetadata, NoLinks>
 
 // Create a typealias for a Document because we do not expect

JSONAPI.playground/Sources/Entities.swift

@@ -25,7 +25,7 @@ extension String: CreatableRawIdType {
 
 // MARK: - typealiases for convenience
 public typealias ExampleEntity<Description: ResourceObjectDescription> = ResourceObject<Description, NoMetadata, NoLinks, String>
-public typealias ToOne<E: Identifiable> = ToOneRelationship<E, NoMetadata, NoLinks>
+public typealias ToOne<E: JSONAPIIdentifiable> = ToOneRelationship<E, NoMetadata, NoLinks>
 public typealias ToMany<E: Relatable> = ToManyRelationship<E, NoMetadata, NoLinks>
 
 // MARK: - A few resource objects (entities)