Merge pull request #16148 from overleaf/jdt-grammarly-promo-wording

update grammarly promo wording

GitOrigin-RevId: 2c1e57fae0c835da322e61f193467078b950c7f5

services/web/frontend/js/features/source-editor/components/grammarly-advert.tsx

@@ -49,7 +49,7 @@ export default function GrammarlyAdvert() {
         <div className="advert-content">
           <p>
             Overleafers get a limited-time 30% discount on Grammarly Premium.
-            (Hurry! Offer ends December 16.)
+            (Hurry! Offer ends December 15.)
           </p>
           <a
             className="advert-link"