update nacos example & using final replace of protected in field

spring-cloud-alibaba-examples/nacos-example/nacos-discovery-example/nacos-discovery-consumer-example/src/main/resources/application.properties

@@ -9,4 +9,5 @@ spring.cloud.sentinel.transport.dashboard=localhost:8080
 spring.cloud.sentinel.eager=true
 
 spring.cloud.sentinel.datasource.ds1.file.file=classpath: flowrule.json
-spring.cloud.sentinel.datasource.ds1.file.data-type=json
+spring.cloud.sentinel.datasource.ds1.file.data-type=json
+spring.cloud.sentinel.datasource.ds1.file.rule-type=flow

spring-cloud-alibaba-sentinel-datasource/src/main/java/org/springframework/cloud/alibaba/sentinel/datasource/config/AbstractDataSourceProperties.java

@@ -27,7 +27,7 @@ public class AbstractDataSourceProperties {
 	private RuleType ruleType;
 	private String converterClass;
 	@JsonIgnore
-	protected String factoryBeanName;
+	private final String factoryBeanName;
 
 	public AbstractDataSourceProperties(String factoryBeanName) {
 		this.factoryBeanName = factoryBeanName;
@@ -61,10 +61,6 @@ public class AbstractDataSourceProperties {
 		return factoryBeanName;
 	}
 
-	public void setFactoryBeanName(String factoryBeanName) {
-		this.factoryBeanName = factoryBeanName;
-	}
-
 	public void preCheck(String dataSourceName) {
 
 	}