remove jsonschema fallback implementations. fix code that used old co…

…ntent type argument to Encoding constructor

Sources/OpenAPIKit/Content/DereferencedContentEncoding.swift

@@ -72,7 +72,7 @@ extension OpenAPI.Content.Encoding: ExternallyDereferenceable {
         }
 
         let newEncoding = OpenAPI.Content.Encoding(
-            contentType: contentType,
+            contentTypes: contentTypes,
             headers: newHeaders,
             style: style,
             explode: explode,

Sources/OpenAPIKit/Schema Object/JSONSchemaContext.swift

@@ -135,22 +135,6 @@ public protocol JSONSchemaContext {
     var vendorExtensions: [String: AnyCodable] { get }
 }
 
-extension JSONSchemaContext {
-
-    // TODO: Remove the default implementations of the following in v4 of OpenAPIKit.
-    //       They are only here to make their addition non-breaking.
-
-    // Default implementation to make addition of this new property which is only
-    // supposed to be set internally a non-breaking addition.
-    public var inferred: Bool { false }
-
-    // Default implementation to make addition non-breaking
-    public var anchor: String? { nil }
-
-    // Default implementation to make addition non-breaking
-    public var dynamicAnchor: String? { nil }
-}
-
 extension JSONSchema {
     /// The context that applies to all schemas.
     public struct CoreContext<Format: OpenAPIFormat>: JSONSchemaContext, HasWarnings {

Sources/OpenAPIKitCompat/Compat30To31.swift

@@ -214,7 +214,7 @@ extension OpenAPIKit30.OpenAPI.Parameter.SchemaContext: To31 {
 extension OpenAPIKit30.OpenAPI.Content.Encoding: To31 {
     fileprivate func to31() -> OpenAPIKit.OpenAPI.Content.Encoding {
         OpenAPIKit.OpenAPI.Content.Encoding(
-            contentType: contentType,
+            contentTypes: [contentType].compactMap { $0 },
             headers: headers?.mapValues(eitherRefTo31),
             style: style,
             explode: explode,