Update UPGRADIN.INTERNALS

Author: Girgias

UPGRADING.INTERNALS

@@ -47,3 +47,8 @@ PHP 8.1 INTERNALS UPGRADE NOTES
       getColumnMeta(). The type provided here does not need to match the type
       returned by get_col (in fact no corresponding type might exist, e.g. for
       floats). It should be the closest logical equivalent for the column type.
+    - The transaction, set_attribute, quoter, and preparer handler's return type
+      has been formalized to bool instead of int.
+    - The check_liveness handler's return type has been formalized to zend_return
+      instead of int.
+    - The closer, and fetch_error handlers have been voidified.