fix sharding-spring-boot-mybatis-example (#7214)

examples/shardingsphere-jdbc-example/sharding-example/sharding-spring-boot-mybatis-example/src/main/resources/application-master-slave.properties

@@ -28,7 +28,7 @@ spring.shardingsphere.datasource.ds_slave_0.jdbc-url=jdbc:mysql://localhost:3306
 
 spring.shardingsphere.datasource.ds_slave_1.jdbc-url=jdbc:mysql://localhost:3306/demo_ds_slave_1?serverTimezone=UTC&useSSL=false&useUnicode=true&characterEncoding=UTF-8
 
-spring.shardingsphere.rules.master-slave.load-balancers.round_robin.type=ROUND_ROB
+spring.shardingsphere.rules.master-slave.load-balancers.round_robin.type=ROUND_ROBIN
 spring.shardingsphere.rules.master-slave.data-sources.ds_ms.master-data-source-name=ds_master
 spring.shardingsphere.rules.master-slave.data-sources.ds_ms.slave-data-source-names=ds_slave_0,ds_slave_1
 spring.shardingsphere.rules.master-slave.data-sources.ds_ms.load-balancer-name=round_robin