MLE-24489 - Multiple upgrades to prep for Kafka 4

[BillFarber]

Update Gradle to 8.14.3
Upgrade Data Hub to 6.2.1
Upgrade to MarkLogic 12
Require Java 17

[Copilot]

Pull Request Overview

This PR upgrades core dependencies to prepare for Kafka 4 compatibility, including Gradle, MarkLogic Data Hub, MarkLogic Server, and Java runtime requirements.

• Updates Gradle from 8.11/8.4 to 8.14.3 across the project
• Upgrades MarkLogic Data Hub from 6.0.0 to 6.2.1
• Migrates from MarkLogic 11 to MarkLogic 12 and Java 11/17 to Java 17 only

Reviewed Changes

Copilot reviewed 9 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
gradle/wrapper/gradle-wrapper.properties	Updates Gradle wrapper to version 8.14.3
test-app/gradle/wrapper/gradle-wrapper.properties	Updates test app Gradle wrapper to version 8.12.1
test-app/gradlew	Updates Gradle wrapper script with improved error handling and POSIX compliance
test-app/gradlew.bat	Updates Windows Gradle wrapper script with license header and improved error output
test-app/build.gradle	Upgrades MarkLogic Data Hub plugin from 6.0.0 to 6.2.1
test-app/.env	Adds environment variable for MarkLogic 12 Docker image
test-app/docker-compose.yml	Removes deprecated version field and uses environment variable for MarkLogic image
Jenkinsfile	Updates Jenkins pipeline to use Java 17 instead of Java 11
CONTRIBUTING.md	Updates documentation to reflect Java 17 requirement and adds Data Hub upgrade notes

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[rjrudin]

Looks good, but can you do a follow up PR with these changes:

1. Move docker-compose.yml and .env to the top of the repo to match our other repo's.
2. Get rid of the gradle wrapper in the test-app directory and instead create a settings.gradle file that includes test-app so that we only have one Gradle wrapper in use.