Bump org.springframework.boot:spring-boot-dependencies in /examples

Bumps [org.springframework.boot:spring-boot-dependencies](https://github.com/spring-projects/spring-boot) from 2.7.14 to 2.7.15.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v2.7.14...v2.7.15)

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

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

examples/javadoc/build.gradle

@@ -3,7 +3,7 @@ apply plugin: "io.freefair.javadocs"
 apply plugin: "io.freefair.github.dependency-manifest"
 
 dependencies {
-    implementation platform("org.springframework.boot:spring-boot-dependencies:2.7.14")
+    implementation platform("org.springframework.boot:spring-boot-dependencies:2.7.15")
     implementation "org.springframework.boot:spring-boot-starter-data-jpa"
     implementation "org.springframework.boot:spring-boot-starter-web"
 }