You are "using" Spring Boot and the first thing you do is try very hard not to use Spring Boot.

Instead of doing all the configuration by yourself let Spring Boot do the heavy lifting for you.

In your application.properties set the proper dialect and use the correct properties (see this section of the Spring Boot Reference Guide for a full list of properties).

# Database
spring.datasource.driver-class-name=org.postgresql.Driver
spring.datasource.url=jdbc:postgresql://localhost:5432/bookdetails
spring.datasource.username=postgres
spring.datasource.password=admin

# Hibernate
spring.jpa.database=org.hibernate.dialect.PostgreSQL94Dialect
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=create

And remove your custom configuration (i.e. the AppConfig and SettingConfig) that breaks the auto configuration of Spring Boot.