update 优化 删除 demo 模块无用 mysql依赖

ruoyi-example/ruoyi-demo/pom.xml

@@ -35,12 +35,6 @@
             <artifactId>spring-boot-starter-actuator</artifactId>
         </dependency>
 
-        <!-- Mysql Connector -->
-        <dependency>
-            <groupId>mysql</groupId>
-            <artifactId>mysql-connector-java</artifactId>
-        </dependency>
-
         <dependency>
             <groupId>com.ruoyi</groupId>
             <artifactId>ruoyi-common-sentinel</artifactId>