fix(deps): update spring boot to v3.5.12

Author: renovate[bot]

server/build.gradle

@@ -1,5 +1,5 @@
 plugins {
-    id 'org.springframework.boot' version '3.5.7' apply false
+    id 'org.springframework.boot' version '3.5.12' apply false
     id 'io.spring.dependency-management' version '1.1.7'
     id 'io.freefair.lombok' version '8.13.1' apply false
     id 'java'

server/helios-status-spring-starter/pom.xml

@@ -20,7 +20,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 
-        <spring.boot.version>3.5.7</spring.boot.version>
+        <spring.boot.version>3.5.12</spring.boot.version>
 
         <!-- dependencies -->
         <lombok.version>1.18.38</lombok.version>