Add WNP 134 (fixes #15750)

[alexgibson]

One-line summary

Adds WNP for Firefox 134, targeting en-US, en-CA, en-GB, de, and fr.

Significant changes and points to review

• Each language get a 50/50 split traffic cop test variation.
• Each variation gets a different QRCode.

Issue / Bugzilla link

#15750

Testing

• http://localhost:8000/en-US/firefox/134.0/whatsnew/
• http://localhost:8000/en-US/firefox/134.0/whatsnew/?v=1
• http://localhost:8000/en-US/firefox/134.0/whatsnew/?v=2
• http://localhost:8000/en-CA/firefox/134.0/whatsnew/
• http://localhost:8000/en-CA/firefox/134.0/whatsnew/?v=1
• http://localhost:8000/en-CA/firefox/134.0/whatsnew/?v=2
• http://localhost:8000/en-GB/firefox/134.0/whatsnew/
• http://localhost:8000/en-GB/firefox/134.0/whatsnew/?v=1
• http://localhost:8000/en-GB/firefox/134.0/whatsnew/?v=2
• http://localhost:8000/de/firefox/134.0/whatsnew/
• http://localhost:8000/de/firefox/134.0/whatsnew/?v=1
• http://localhost:8000/de/firefox/134.0/whatsnew/?v=2
• http://localhost:8000/fr/firefox/134.0/whatsnew/
• http://localhost:8000/fr/firefox/134.0/whatsnew/?v=1
• http://localhost:8000/fr/firefox/134.0/whatsnew/?v=2

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.10%. Comparing base (a2eb92c) to head (8c9187e).
Report is 8 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15779      +/-   ##
==========================================
+ Coverage   79.07%   79.10%   +0.03%     
==========================================
  Files         160      160              
  Lines        8359     8371      +12     
==========================================
+ Hits         6610     6622      +12     
  Misses       1749     1749              

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[alexgibson]

This is just about ready for code review, but adding a DMN label for now - in case there's anything left we still need to add.

[craigcook]

🦊