Bug #96227 please make innodb_read_io_threads and innodb_write_io_threads dynamic

Description:
To avoid downtime and to ease testing,  please make these settings dynamic:

mysql> set global innodb_read_io_threads=8;
ERROR 1238 (HY000): Variable 'innodb_read_io_threads' is a read only variable
mysql> set global innodb_write_io_threads=8;
ERROR 1238 (HY000): Variable 'innodb_write_io_threads' is a read only variable
mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.16    |
+-----------+
1 row in set (0.00 sec)

How to repeat:
set global innodb_read_io_threads=8;
set global innodb_write_io_threads=8;

Yes please.