You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: destroy_service.rb
    path of file: ./repos/gitlabhq/app/services/issuable_links
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

module IssuableLinks
  class DestroyService < BaseService
    attr_
    
    def execute
      return error(not_found_message, 404) unless permission_to_remove_relation?

      remove_relation
      after_destroy

      success(message: 'Relation was removed')
    end