Update Spring Boot and Mysql version for react-java-mysql sample

Signed-off-by: Guillaume Lours <guillaume.lours@docker.com>

react-java-mysql/backend/src/main/resources/application.properties

@@ -1 +1,12 @@
+spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL8Dialect
+spring.jpa.hibernate.ddl-auto=none
+spring.jpa.hibernate.show-sql=true
 
+
+spring.datasource.url=jdbc:mysql://${MYSQL_HOST:db}:3306/example
+spring.datasource.username=root
+spring.datasource.password=${MYSQL_PASSWORD:db-57xsl}
+spring.datasource.initialization-mode=always
+spring.datasource.initialize=true
+spring.datasource.schema=classpath:/schema.sql
+spring.datasource.continue-on-error=true