when both jdbcUrl and dataSourceClassName are set, dataSourceClassName has the higher priority during setup and
it requires setting all the necessary related properties. HikariCP will not validate config (newly fixed, see [1])
and silently initialize an 'empty' data source which fails during runtime. this fix drops the usage of jdbcUrl,
and properly and fully sets the data source properties.

[1] https://github.com/brettwooldridge/HikariCP/issues/401