Fixup #12892 - replace marked text with highlighted text

[seanbudd]

Link to issue number:

Follow up of #12892

Summary of the issue:

A usage of "marked text" still remains, while other usages have been replaced with "highlighted text"

Description of how this pull request fixes the issue:

Replaces marked text with highlighted text

Testing strategy:

None

Known issues with pull request:

None

Change log entries:

None needed

Code Review Checklist:

• Pull Request description:
  • description is up to date
  • change log entries
• Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• API is compatible with existing add-ons.
• Documentation:
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English