update springboot 3.5.4 => 3.5.6

pom.xml

@@ -17,7 +17,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>17</java.version>
-        <spring-boot.version>3.5.4</spring-boot.version>
+        <spring-boot.version>3.5.6</spring-boot.version>
         <spring-cloud.version>2025.0.0</spring-cloud.version>
         <spring-boot-admin.version>3.5.3</spring-boot-admin.version>
         <mybatis.version>3.5.16</mybatis.version>