Fix specs by passing required user

spec/lib/api/v3/work_packages/work_package_model_spec.rb

@@ -31,8 +31,9 @@ require 'spec_helper'
 describe ::API::V3::WorkPackages::WorkPackageModel do
   include Capybara::RSpecMatchers
 
-  subject(:model) { ::API::V3::WorkPackages::WorkPackageModel.new(work_package) }
+  subject(:model) { ::API::V3::WorkPackages::WorkPackageModel.new(work_package, current_user) }
   let(:work_package) { FactoryGirl.build(:work_package, attributes) }
+  let(:current_user) { FactoryGirl.build(:user) }
 
   context 'with a formatted description' do
     let(:attributes) {

spec/lib/api/v3/work_packages/work_package_representer_spec.rb

@@ -34,7 +34,7 @@ describe ::API::V3::WorkPackages::WorkPackageRepresenter do
 
   let(:representer)  { described_class.new(model, current_user: current_user) }
 
-  let(:model)        { ::API::V3::WorkPackages::WorkPackageModel.new(work_package) }
+  let(:model)        { ::API::V3::WorkPackages::WorkPackageModel.new(work_package, current_user) }
   let(:work_package) { FactoryGirl.build(:work_package,
       id: 42,
       created_at: DateTime.now,