add nextcloud app update to upgrade script

utils/upgrade.sh

@@ -268,6 +268,10 @@ if command -v docker >/dev/null 2>&1; then
                     fi
                 )
                 ;;
+            nextcloud:*)
+                docker pull "$image"
+                docker exec -it nextcloud php occ app:update --all
+                ;;
             *"<none>"*)
                 ;;
             *)