update pom.xml

pom.xml

@@ -18,6 +18,7 @@
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>1.8</java.version>
         <maven-jar-plugin.version>3.1.1</maven-jar-plugin.version>
+        <spring-boot.version>2.5.15</spring-boot.version>
         <druid.version>1.2.23</druid.version>
         <bitwalker.version>1.21</bitwalker.version>
         <swagger.version>3.0.0</swagger.version>
@@ -62,7 +63,7 @@
             <dependency>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-dependencies</artifactId>
-                <version>2.5.15</version>
+                <version>${spring-boot.version}</version>
                 <type>pom</type>
                 <scope>import</scope>
             </dependency>