add deprecation messages

Author: yaacovCR

src/type/definition.ts

@@ -1055,6 +1055,7 @@ export interface GraphQLArgumentExtensions {
 export interface GraphQLArgumentConfig {
   description?: Maybe<string>;
   type: GraphQLInputType;
+  /** @deprecated use externalDefaultValue instead, defaultValue will be removed in v17 **/
   defaultValue?: unknown;
   externalDefaultValue?: unknown;
   defaultValueLiteral?: ConstValueNode | undefined;
@@ -1791,6 +1792,7 @@ export interface GraphQLInputFieldExtensions {
 export interface GraphQLInputFieldConfig {
   description?: Maybe<string>;
   type: GraphQLInputType;
+  /** @deprecated use externalDefaultValue instead, defaultValue will be removed in v17 **/
   defaultValue?: unknown;
   externalDefaultValue?: unknown;
   defaultValueLiteral?: ConstValueNode | undefined;