upgraded spring-boot to 3.5.6

Author: rmmayo

java-backend-example/pom.xml

@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>3.5.5</version>
+        <version>3.5.6</version>
         <relativePath/> <!-- lookup parent from repository -->
     </parent>
     <groupId>skill-tree</groupId>