restapi routes does not persist when loading from config

[mholmbergC]

reproducible bug for ProxySQL.
- description: when loading restapi from proxysql.cnf.. its loads just fine, however if I restart the proxysql process.. it loosing all restapi_routes.. while all the other settings from proxysql.cnf remains.

- ProxySQL version: 2.5.1
- OS version: redhat + debian
- The steps to reproduce the issue

rm -Rf /var/lib/proxysql/proxysql*
systemctl restart proxysql
mysql -h 127.0.0.1 -P 6032 -uproxysql-admin -p** --prompt='Admin> '

Admin>  SELECT * FROM restapi_routes;
+----+--------+------------+--------+----------------+--------------------------------+---------+
| id | active | timeout_ms | method | uri            | script                         | comment |
+----+--------+------------+--------+----------------+--------------------------------+---------+
| 1  | 1      | 1000       | GET    | add_user       | /opt/restapi/add_user.sh       | comment |
| 2  | 1      | 1000       | GET    | del_user       | /opt/restapi/del_user.sh       | comment |
| 3  | 1      | 1000       | GET    | get_user       | /opt/restapi/get_user.sh       | comment |
 comment |
+----+--------+------------+--------+----------------+--------------------------------+---------+
3 rows in set (0.00 sec)

Admin> exit
systemctl restart proxysql
mysql -h 127.0.0.1 -P 6032 -uproxysql-admin -p** --prompt='Admin> '
Admin> SELECT * FROM restapi_routes;
Empty set (0.00 sec)
-------
if I do before restarting.. it get stored persisted.
load restapi to runtime;
save restapi to disk;

I would just expect that restapi_routes loaded from config would behave the same as rest of the settings. Just like to not have the manually go in on each node and save this.

Thank you!

[renecannao]

Solved in PR #4187