Spring Broken guide : Accessing data with MySQL in spring.io

I import project "complete" from "Accessing data with MySQL" in Android Studio and everything looks fine. But when i close the project and open it again, i take the following error message:

APPLICATION FAILED TO START

Description: Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured. Reason: Failed to determine a suitable driver class Action: Consider the following: If you want an embedded database (H2, HSQL or Derby), please put it on the classpath. If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

What is wrong with this project. It should be a running guide. https://spring.io/guides/gs/accessing-data-mysql/

Comment From: bclozel

Please use the dedicated repository for issues. Thanks! https://github.com/spring-guides/gs-accessing-data-mysql/issues