build(deps): Bump springboot.version from 4.0.3 to 4.0.4

Bumps `springboot.version` from 4.0.3 to 4.0.4.

Updates `org.springframework.boot:spring-boot-maven-plugin` from 4.0.3 to 4.0.4
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v4.0.3...v4.0.4)

Updates `org.springframework.boot:spring-boot-starter-web` from 4.0.3 to 4.0.4
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v4.0.3...v4.0.4)

Updates `org.springframework.boot:spring-boot-starter-test` from 4.0.3 to 4.0.4
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v4.0.3...v4.0.4)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-maven-plugin
  dependency-version: 4.0.4
  dependency-type: direct:development
  update-type: version-update:semver-patch
- dependency-name: org.springframework.boot:spring-boot-starter-web
  dependency-version: 4.0.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: org.springframework.boot:spring-boot-starter-test
  dependency-version: 4.0.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

pom.xml

@@ -167,7 +167,7 @@
     <moshi.version>1.15.2</moshi.version>
     <slf4j.version>2.0.17</slf4j.version>
     <json.version>20251224</json.version>
-    <springboot.version>4.0.3</springboot.version>
+    <springboot.version>4.0.4</springboot.version>
 
     <junit5.version>6.0.3</junit5.version>
     <jackson.version>2.21.1</jackson.version>