Fixed DSpace metadata duplication on update

Gemfile

@@ -39,7 +39,7 @@ gem 'rack-cors', require: 'rack/cors'
 gem 'rmagick'
 
 # Dspace REST API Integration
-gem 'dspace_rest_client', github: 'mgiacomini/dspace-rest-client', branch: 'master'
+gem 'dspace_rest_client', github: 'c3sl/dspace-rest-client', branch: 'master'
 
 # pretty logs
 gem 'rainbow'

app/services/learning_object_publisher.rb

@@ -68,7 +68,7 @@ class LearningObjectPublisher
         metadata << { 'key' => key, 'value' => v, 'language' => object.language.try(:code) || 'pt' } unless v.blank?
       end
     end
-    @dspace.items.add_metadata(metadata, id: object.id_dspace) unless metadata.empty?
+    @dspace.items.update_metadata(metadata, id: object.id_dspace) unless metadata.empty?
   end
 
   private