Bump org.mockito:mockito-core from 5.12.0 to 5.15.2

Bumps [org.mockito:mockito-core](https://github.com/mockito/mockito) from 5.12.0 to 5.15.2.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](mockito/mockito@v5.12.0...v5.15.2)

---
updated-dependencies:
- dependency-name: org.mockito:mockito-core
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

core/build.gradle

@@ -41,7 +41,7 @@ dependencies {
     implementation 'com.codingrodent:jackson-json-crypto:1.1.0'
 
     testImplementation "junit:junit:4.13.2"
-    testImplementation "org.mockito:mockito-core:5.12.0"
+    testImplementation "org.mockito:mockito-core:5.15.2"
 
     testImplementation(platform("org.junit:junit-bom:5.10.3"))
     testImplementation "org.junit.jupiter:junit-jupiter-api"