Polish alibaba/spring-cloud-alibaba/#1222 : Resolve the examples issues

spring-cloud-alibaba-examples/spring-cloud-alibaba-sidecar-examples/spring-cloud-alibaba-sidecar-nacos-example/pom.xml

@@ -13,6 +13,12 @@
     <description>Example demonstrating how to use Spring Cloud Alibaba Sidecar with nacos</description>
 
     <dependencies>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-actuator</artifactId>
+        </dependency>
+
         <dependency>
             <groupId>com.alibaba.cloud</groupId>
             <artifactId>spring-cloud-starter-alibaba-sidecar</artifactId>