Fix translation of carousel slides when changing media ID

I was trying to translate the slides that i just deleted before.

pkg/carousel/admin.go

@@ -238,6 +238,7 @@ func editSlide(w http.ResponseWriter, r *http.Request, user *auth.User, company
 			if _, err := tx.Exec(ctx, fmt.Sprintf("select remove_%s_carousel_slide($1)", f.CarouselName), f.ID); err != nil {
 				return err
 			}
+			f.ID = f.Media.Int() // for translateSlide
 		}
 		return translateSlide(ctx, tx, company, f)
 	})