MDEV-37724: Debug Memory leak with InnoDB ALTER TABLE ALGORITHM=INSTANT

Instrumented debug mode triggering of instant_insert_fail
failed to free partition memory like the que_eval_sql function
who's failure it intended to emulate.

Corrected by freeing the partition information when this internal
debug mode instrumented condition occured.

Author: grooverdan

storage/innobase/handler/handler0alter.cc

@@ -5528,6 +5528,7 @@ static bool innodb_insert_sys_columns(
 	DBUG_EXECUTE_IF("instant_insert_fail",
 			my_error(ER_INTERNAL_ERROR, MYF(0),
 				 "InnoDB: Insert into SYS_COLUMNS failed");
+			pars_info_free(info);
 			return true;);
 
 	if (DB_SUCCESS != que_eval_sql(