Better support i18n in entity_date_helper#remaining_days_in_words
Description
Discussed in a previous MR:
Not introduced by this MR but I just wanted to point out that this isn't i18n-friendly: here we assume all languages are structured similarly to the English, i.e. "x days remaining" but translating "remaining" alone doesn't make sense, what if I want to say "Il reste x jours" in French... More at https://docs.gitlab.com/ee/development/i18n/externalization.html#splitting-sentences.
Proposal
Refactor remaining_days_in_words
to be able to support all languages when representing remaining days in words.
Links / references
https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/5212#note_68778911