Add copyWith deps to pubspec mustache template

Author: LahaLuhem

modules/openapi-generator/src/main/resources/dart/libraries/dio/pubspec.mustache

@@ -25,6 +25,7 @@ dependencies:
   equatable: '^2.0.7'
 {{/useEquatable}}
 {{#useJsonSerializable}}
+  copy_with_extension: '^7.1.0'
   json_annotation: '^4.9.0'
 {{/useJsonSerializable}}
 {{#useDateLibTimeMachine}}
@@ -38,6 +39,7 @@ dev_dependencies:
 {{/useBuiltValue}}
 {{#useJsonSerializable}}
   build_runner: any
+  copy_with_extension_gen: ^7.1.0
   json_serializable: '^6.9.3'
 {{/useJsonSerializable}}
   test: '^1.16.0'