Fix extra i18n namespacing

[whithajess]

Fixes: #290

[codecov]

Codecov Report

Merging #293 (d739c8b) into master (c178c6f) will not change coverage.
The diff coverage is 100.00%.

❗ Current head d739c8b differs from pull request most recent head 289ea67. Consider uploading reports for the commit 289ea67 to get more accurate results

@@            Coverage Diff            @@
##            master      #293   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           25        25           
  Lines          537       537           
=========================================
  Hits           537       537           

Impacted Files	Coverage Δ
lib/pagy/extras/i18n.rb	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update c178c6f...289ea67. Read the comment docs.

[ddnexus]

Thank you!