Evaluate which translation strings are still used

[moorscode]

The strings/translations in the following location need to be checked, because most of them are not used anymore and are translated in yoast-components.

https://github.com/Yoast/wordpress-seo/blob/943631a83a0dda2771510cff63b991434a83458e/admin/formatter/class-metabox-formatter.php#L156

Because these are slightly different, they appear as different strings in translate.wordpress.org, thus will take time to get translated.

[moorscode]

Original issue: https://github.com/Yoast/wordpress-seo/issues/10842

[atimmer]

These can all be simply removed because we now parse the JavaScript for strings that need to be translated instead of duplicating the strings in PHP.

[mhkuu]

Fixed through #21386 👍