Add spec for Assigned Articles view and Feedback feature
user
```ruby
# frozen_string_literal: true

require 'rails_helper'

describe 'Assigned Articles view', type: :feature, js: true do
  let(:course) { create(:course) }
  let(:user) { create(:user, username: 'Ragesoss') }
  let(:article) { create(:article, title: 'Nancy_Tuana') }

  before do
    login_as(user)
    course.campaigns << Campaign.first
    create(:courses_user, course: course, user: user)
    create(:assignment, article_title: 'Nancy_Tuana',
                        course: course, article: article,
                        user: user)
  end

  it 'lets users submit feedback about articles' do
    # Since this makes a call to the ORES API from the server,
    # we need to use VCR to avoid getting stopped by WebMock
    VCR.use_cassette('assigned_articles_view') do
      visit "/courses/#{course.slug}/articles/assigned"
      expect(page).to have_content('Nancy Tuana')
      find('a', text: 'Feedback').click
      find('textarea.feedback-form').fill_in with: 'This is a great article!'
      click_button 'Add Suggestion'
      find('a', text: 'Delete').click
      expect(page).not_to have_content('This is a great article!')
    end
  end
end
```
assistant