Bump org.assertj:assertj-core (opensearch-project#6460)

Bumps [org.assertj:assertj-core](https://github.com/assertj/assertj) from 3.27.3 to 3.27.7.
- [Release notes](https://github.com/assertj/assertj/releases)
- [Commits](assertj/assertj@assertj-build-3.27.3...assertj-build-3.27.7)

---
updated-dependencies:
- dependency-name: org.assertj:assertj-core
  dependency-version: 3.27.7
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

data-prepper-plugins/otel-metrics-raw-processor/build.gradle

@@ -21,7 +21,7 @@ dependencies {
     implementation 'com.fasterxml.jackson.core:jackson-databind'
     implementation 'com.fasterxml.jackson.dataformat:jackson-dataformat-yaml'
     implementation libs.guava.core
-    testImplementation 'org.assertj:assertj-core:3.27.3'
+    testImplementation 'org.assertj:assertj-core:3.27.7'
 }
 
 jacocoTestCoverageVerification {