Added if/else block for correct i18n extraction

[merwhite11]

Closes # Addendum to: https://github.com/internetarchive/openlibrary/pull/8981

Eliminates the need for a hard-coded-in-English variable here: https://github.com/internetarchive/openlibrary/pull/8981#discussion_r1560346611

Technical

Added an if/else block ...repeats syntax, but extracts correctly in .pot

Testing

Ran docker compose run --rm -uroot home ./scripts/i18n-messages extract to ensure message extracted correctly.

Screenshot

Stakeholders

@cdrini