Update UPGRADING

Author: kamil-tekiela

UPGRADING

@@ -882,6 +882,10 @@ PHP 8.4 UPGRADE NOTES
   . The MYSQLI_CURSOR_TYPE_FOR_UPDATE and MYSQLI_CURSOR_TYPE_SCROLLABLE
     constants have been removed. This functionality was never implemented,
     neither with mysqlnd nor with libmysql.
+  . A new constant has been added: MYSQLI_TYPE_VECTOR.
+
+- Mysqlnd
+  . Support for the new VECTOR data type from MySQL 9.
 
 - OpenSSL:
   . The OpenSSL extension now requires at least OpenSSL 1.1.1.