spring.datasource.url= jdbc:mysql://${MYSQL_URL}:${MYSQL_PORT}/${MYSQL_DBNAME}
spring.datasource.username= ${MYSQL_USERNAME}
spring.datasource.password= ${MYSQL_PASSWORD}
spring.datasource.driver-class-name= com.mysql.jdbc.Driver
spring.jpa.hibernate.ddl-auto= update
spring.jpa.properties.hibernate.dialect= org.hibernate.dialect.MySQL5Dialect

Property: spring.datasource.url
    Value: jdbc:mysql://${MYSQL_URL}:${MYSQL_PORT}/${MYSQL_DBNAME}
    Origin: class path resource [application.properties]:1:24
    Reason: Could not resolve placeholder 'MYSQL_URL' in value "jdbc:mysql://${MYSQL_URL}:${MYSQL_PORT}/${MYSQL_DBNAME}"