Bump org.springframework.boot from 3.5.7 to 4.0.0

Bumps [org.springframework.boot](https://github.com/spring-projects/spring-boot) from 3.5.7 to 4.0.0.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v3.5.7...v4.0.0)

---
updated-dependencies:
- dependency-name: org.springframework.boot
  dependency-version: 4.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

server/build.gradle

@@ -14,7 +14,7 @@ buildscript {
 plugins {
     id 'java'
     id 'idea'
-    id 'org.springframework.boot' version '3.5.7'
+    id 'org.springframework.boot' version '4.0.0'
     id 'jacoco'
 }