Move stub_packages_object_storage to ee helper

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

ee/spec/support/helpers/ee/stub_object_storage.rb

+module EE
+  module StubObjectStorage
+    def stub_packages_object_storage(**params)
+      stub_object_storage_uploader(config: ::Gitlab.config.packages.object_store,
+                                   uploader: ::Packages::PackageFileUploader,
+                                   remote_directory: 'packages',
+                                   **params)
+    end
+  end
+end

spec/support/helpers/stub_object_storage.rb

 module StubObjectStorage
+  prepend EE::StubObjectStorage
+
   def stub_object_storage_uploader(
         config:,
         uploader:,
@@ -72,11 +74,4 @@ module StubObjectStorage
     stub_object_storage(connection_params: Pseudonymizer::Uploader.object_store_credentials,
                         remote_directory: Pseudonymizer::Uploader.remote_directory)
   end
-
-  def stub_packages_object_storage(**params)
-    stub_object_storage_uploader(config: Gitlab.config.packages.object_store,
-                                 uploader: ::Packages::PackageFileUploader,
-                                 remote_directory: 'packages',
-                                 **params)
-  end
 end