update date formatin title of release notification

Signed-off-by: dartcafe <github@dartcafe.de>

.github/RELEASE_NOTIFICATION.md

@@ -1,5 +1,5 @@
 ---
-title: Polls {{ env.VERSION }} released ({{ date | date('DD-MM-YYYY') }})
+title: Polls {{ env.VERSION }} released ({{ date | date('YYYY-MM-DD') }})
 labels: Announcement
 ---
 # Releasenotes {{ env.VERSION }}