Looks like more problems to connect to your database, not that it cannot connect to localhost. Try to add driver, looks like it's missing. Your error says "Failed to determine DatabaseDriver". Add "spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver".

Also pay attention to spring.jpa.hibernate.ddl-auto=update. Make sure, when you first time run application and want to create database for the first time to do spring.jpa.hibernate.ddl-auto=create. After its created, I normally change to spring.jpa.hibernate.ddl-auto=update and then the new modifications of database is updated during the further work.