Made two messages translatable.

[CyrilleB79]

Link to issue number:

Reported on the translator's mailing list in this thread.

Summary of the issue:

PR #13798 introduced paragraph navigation in documents. Unfortunately two message added by this PR are not translatable: "No next/previous paragraph" since the gettext (_) function call has been forgotten; the translators comments are already there though.

Description of user facing changes

The message will be translatable

Description of development approach

Just added the call to the gettext function (_).

Testing strategy:

Manual:
Generate a .pot, merge to .po in French, translate it and use it with the feature.

Known issues with pull request:

While at it, I have searched for other occurrences of ui.message called with untranslated content. In NVDAObjects/IAccessible/winword.py, in the script script_reportCurrentHeaders, I have found:
ui.message("Row %s, column %s"%(rowText or "empty",columnText or "empty"))

I have not fixed this as this script is a half buggy, half debug and undocumented script (see #11465 for details).

Change log entries:

New features
Changes
Bug fixes
For Developers

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
• Security precautions taken.

Cc @rob-aph