Eu baixei o jar instalura.jar de https://github.com/alberto-alura/instalura-api. Quando executo o comando "java -jar instalura.jar" eu recebo o erro abaixo. Meu java é o 8 (oracle). Existe a API online para que eu possa usar? Estou travado no curso. Ajudem por favor.

ERRO RECEBIDO:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaAutoConfiguration.class]: Invocation of init method failed; nested exception is org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]

Caused by: org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]

Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set