Revert #5438 for FR (#5450)

As said here https://github.com/tootsuite/mastodon/pull/5438 the point of shortening the timestamp is legit, and after some time of adaptation no mistakes can be mades.

app/javascript/mastodon/locales/fr.json

@@ -159,11 +159,11 @@
   "privacy.public.short": "Public",
   "privacy.unlisted.long": "Ne pas afficher dans les fils publics",
   "privacy.unlisted.short": "Non-listé",
-  "relative_time.days": "il y a {number} j",
-  "relative_time.hours": "il y a {number} h",
+  "relative_time.days": "{number} j",
+  "relative_time.hours": "{number} h",
   "relative_time.just_now": "à l’instant",
-  "relative_time.minutes": "il y a {number} min",
-  "relative_time.seconds": "il y a {number} s",
+  "relative_time.minutes": "{number} min",
+  "relative_time.seconds": "{number} s",
   "reply_indicator.cancel": "Annuler",
   "report.placeholder": "Commentaires additionnels",
   "report.submit": "Envoyer",