SpringBoot DataSource auto-configuration does not use the driver class name from JdbcConnectionDetails

As reported by @eddumelendez in https://github.com/spring-projects/spring-boot/issues/34760, DataSource auto-configuration ignores the connection details' driver class name so it infers the driver from the JDBC URL instead. This results in a failure when the driver isn't known to org.springframework.boot.jdbc.DatabaseDriver.