MERGE TO FEATURE BRANCH - 214 - Test Header and Search - MERGE FIRST

[Janell-Huyck]

This PR continues the modular feature testing path by including tests for what should and should not be included in the header. It also adds in checks for the functionality of the search box by title and item number, since the search box is inside the header.

File changes:

• spec/features/end_to_end_spec.rb
  • remove checks of the search box, as this is now done in modular test
• spec/features/specs/user_scenarios/admin_user_spec.rb
  • add check for admin_user header
• spec/features/specs/user_scenarios/non_authenticated_user_spec.rb
  • add check for non-authenticated user header
• spec/features/specs/user_scenarios/read_only_user_spec.rb
  • add check for read-only user header
• spec/features/specs/user_scenarios/standard_user_spec.rb
  • add check for standard user header
• spec/features/support/helpers/unauthorized_access_helpers.rb
  • remove duplicated call to frozen string literal
• spec/features/support/shared_examples/header_checks/admin_user_header_check.rb
  • new file - tests for admin header
• spec/features/support/shared_examples/header_checks/non_authenticated_user_header_check.rb
  • new file - tests for non-authenticated user header
• spec/features/support/shared_examples/header_checks/read_only_user_header_check.rb
  • new file - tests for read-only-user header
• spec/features/support/shared_examples/header_checks/search_area_functionality_check.rb
  • new file - tests presence and functioning of the search area
• spec/features/support/shared_examples/header_checks/standard_user_header_check.rb
  • new file - tests for standard user's header