Bump org.mockito:mockito-bom from 5.20.0 to 5.21.0 (#395)

Bumps [org.mockito:mockito-bom](https://github.com/mockito/mockito) from 5.20.0 to 5.21.0.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](mockito/mockito@v5.20.0...v5.21.0)

---
updated-dependencies:
- dependency-name: org.mockito:mockito-bom
  dependency-version: 5.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

internal-bom/build.gradle.kts

@@ -13,7 +13,7 @@ dependencies {
     api(platform("org.junit:junit-bom:6.0.1"))
     api(platform("org.testcontainers:testcontainers-bom:1.21.3"))
     api(platform("io.github.mfvanek:pg-index-health-bom:0.30.2"))
-    api(platform("org.mockito:mockito-bom:5.20.0"))
+    api(platform("org.mockito:mockito-bom:5.21.0"))
     api(platform("org.assertj:assertj-bom:3.27.6"))
 
     constraints {