bug #890 Sufix translations files with +intl-icu (gmsantos)

This PR was squashed before being merged into the master branch (closes #890).

Discussion
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Sufix translations files with +intl-icu

~~Also added intl extension to composer require because when I was testing on my machine, this extension was missing.~~

Reverting intl extension require in favor of #895

Maybe we could require [`polyfill-intl-normalizer`](https://github.com/symfony/polyfill-intl-normalizer) instead of the extension.

Commits
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888897b Sufix translations files with +intl-icu

Author: javiereguiluz