Fix helper first_line() for newline pattern to match

app/helpers/application_helper.rb
- Fix RE_NEWLINE for first_line().
Modify 'approval_statuses#index' in font color for readability

app/assets/stylesheets/style.css
- Add color of white to
  '#table_ad_hoc_works_approval_status .Finished',
  '#table_ad_hoc_works_approval_status .Not_Approved',
  and '#table_work_plans_approval_status .finished'.