fix(metadata): remove the default type to work around a TS bug

See microsoft/TypeScript#26985

Author: raymondfeng

packages/authentication/src/keys.ts

@@ -105,5 +105,6 @@ export namespace AuthenticationBindings {
  * The key used to store log-related via @loopback/metadata and reflection.
  */
 export const AUTHENTICATION_METADATA_KEY = MetadataAccessor.create<
-  AuthenticationMetadata
+  AuthenticationMetadata,
+  MethodDecorator
 >('authentication.operationsMetadata');

packages/metadata/src/types.ts

@@ -30,7 +30,7 @@ export class MetadataAccessor<T, D extends DecoratorType = DecoratorType> {
    * @typeparam T Type of the metadata value
    * @typeparam D Type of the decorator
    */
-  static create<T, D extends DecoratorType = DecoratorType>(key: string) {
+  static create<T, D extends DecoratorType>(key: string) {
     return new MetadataAccessor<T, D>(key);
   }
 }

packages/repository-json-schema/src/keys.ts

@@ -9,6 +9,7 @@ import {JSONSchema6 as JSONSchema} from 'json-schema';
 /**
  * Metadata key used to set or retrieve repository JSON Schema
  */
-export const JSON_SCHEMA_KEY = MetadataAccessor.create<JSONSchema>(
-  'loopback:json-schema',
-);
+export const JSON_SCHEMA_KEY = MetadataAccessor.create<
+  JSONSchema,
+  ClassDecorator
+>('loopback:json-schema');