How to define timezone in mariadb testcontainer accessed via r2dbc:tc:mariadb

[aabeling]

I am able to start a mariadb testcontainer with a jdbc url like r2dbc:tc:mariadb:///workflow?TC_IMAGE_TAG=10.6.21.
But it does not have the correct timezone I need for my application and my tests.
Tests for queries using NOW() make problems.

With jdbc:tc:mysql:8.0.36://hostname/databasename?TC_MY_CNF=somepath/mysql_conf_override it is possible to provide a my.cnf with something like

[mysqld]
default-time-zone = "Europe/Berlin"

The same is possible with jdbc:tc:mariadb.

How can I set the timezone for the database container with "r2dbc"?

#4687 says it does not support TC_INITSCRIPT, but this would not help to set the timezone anyway since the timezone must be defined at the start of the database server.