Add possibility to make reusable containers

[iirekm]

Test containers library has recently added support for withReuse(true), which makes test startup faster, unfortunately I can't find any way to enable this option in this library.

[tomix26]

It should already be possible to enable this option using a container customizer. Just add a bean implementing io.zonky.test.db.provider.postgres.PostgreSQLContainerCustomizer, io.zonky.test.db.provider.mssql.MSSQLServerContainerCustomizer, io.zonky.test.db.provider.mysql.MySQLContainerCustomizer or io.zonky.test.db.provider.mariadb.MariaDBContainerCustomizer based on the database you are currently using.

[tomix26]

More information is here: https://github.com/zonkyio/embedded-database-spring-test#docker-provider-specific-configuration