Fix hanging during text paragraph navigation in UIA edge

[mltony]

Link to issue number:

Closes #16436.

Summary of the issue:

Text paragraph navigation hangs in UIA edge near the end of document.

Description of user facing changes

N/A

Description of development approach

Replaced logic to find next paragraph with already polished function from another PR. It's got a condition that prevents hanging in this case.

Testing strategy:

Tested manually on provided test case.

Known issues with pull request:

N/A

Code Review Checklist:

• [x] Documentation:
  • Change log entry
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• [x] Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• [x] UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English
• [x] API is compatible with existing add-ons.
• [x] Security precautions taken.