Bump io.spring.gradle:spring-security-release-plugin

Bumps [io.spring.gradle:spring-security-release-plugin](https://github.com/spring-io/spring-security-release-tools) from 1.0.14 to 1.0.15.
- [Release notes](https://github.com/spring-io/spring-security-release-tools/releases)
- [Changelog](https://github.com/spring-io/spring-security-release-tools/blob/main/RELEASE.adoc)
- [Commits](spring-io/spring-security-release-tools@v1.0.14...v1.0.15)

---
updated-dependencies:
- dependency-name: io.spring.gradle:spring-security-release-plugin
  dependency-version: 1.0.15
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

buildSrc/build.gradle

@@ -94,7 +94,7 @@ dependencies {
     implementation 'com.github.ben-manes:gradle-versions-plugin:0.53.0'
     implementation 'com.github.spullara.mustache.java:compiler:0.9.14'
     implementation 'io.spring.javaformat:spring-javaformat-gradle-plugin:0.0.47'
-    implementation 'io.spring.gradle:spring-security-release-plugin:1.0.14'
+    implementation 'io.spring.gradle:spring-security-release-plugin:1.0.15'
     implementation 'io.spring.nullability:io.spring.nullability.gradle.plugin:0.0.12'
     implementation 'io.spring.nohttp:nohttp-gradle:0.0.11'
     implementation 'net.sourceforge.htmlunit:htmlunit:2.70.0'