wsrep_provider_options can be truncated on deep and long directory paths

CURRENT_TEST: galera.galera#505

--- /home/jenkins/workspace/mtr-galera-4.x-mariadb-10.5-master/mysql-wsrep/mysql-test/suite/galera/r/galera#505.result	2023-10-09 00:02:23.302042813 +0200

+++ /home/jenkins/workspace/mtr-galera-4.x-mariadb-10.5-master/mysql-wsrep/mysql-test/suite/galera/r/galera#505.reject	2023-10-09 00:21:23.027885060 +0200

@@ -8,4 +8,6 @@

 SHOW GLOBAL VARIABLES LIKE 'wsrep_provider_options';

 Variable_name	Value

 wsrep_provider_options	pc.weight = 3

+Warnings:

+Warning	1265	Data truncated for column 'VARIABLE_VALUE' at row 1

 SET GLOBAL wsrep_provider_options = 'pc.weight=1';