更新 log4j 版本，堵上惊天漏洞

pom.xml

@@ -27,6 +27,7 @@
     </parent>
 
     <properties>
+        <log4j2.version>2.15.0</log4j2.version>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>1.8</java.version>
@@ -49,6 +50,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
+
         </dependency>
 
         <!--Spring boot 测试-->