update README.md.

README.md

@@ -31,7 +31,7 @@
   <plugin>
       <groupId>com.idea-aedi</groupId>
       <artifactId>class-winter-maven-plugin</artifactId>
-      <version>最新版本号</version>
+      <version>2.3.0</version>
       <!-- 相关配置 -->
       <configuration>
           <!-- <finalName></finalName>-->