Add Dutch translations for Djoser messages

[aliokan]

This PR adds Dutch translations.

I use poetry run django-admin makemessages -l nl to generate the file.

This is my first contribution to a Django project, so I welcome any feedback or suggestions for improvement to ensure everything aligns with the project’s standards. Thank you for your guidance! 😊

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.66%. Comparing base (9aa1e82) to head (37fa6ab).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #859   +/-   ##
=======================================
  Coverage   98.66%   98.66%           
=======================================
  Files          27       27           
  Lines         902      902           
=======================================
  Hits          890      890           
  Misses         12       12           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[tomwojcik]

Sorry but it can't be merged as is due to hooks failing. If you want t to be merged, just make init and make run-hooks should be enough.