improve minute return

src/departures-router.mjs

@@ -28,9 +28,11 @@ departuresRouter.get('/departures', (req, res) => {
           return stop.departures.flatMap((d) => d.next);
         })
         .map(Number)
-        .sort();
+        .toSorted((a, b) => a - b);
 
-      return res.json(minutes);
+      const uniqueMinutes = [...new Set(minutes)];
+
+      return res.json(uniqueMinutes);
     }
 
     return res.json(departures);