IGNITE-28482 Revert "IGNITE-28433 Bump gradle-wrapper from 8.6 to 8.14.4"

[sashapolo]

https://issues.apache.org/jira/browse/IGNITE-28482

This reverts commit 826fe8f.

Thank you for submitting the pull request.

To streamline the review process of the patch and ensure better code quality
we ask both an author and a reviewer to verify the following:

The Review Checklist

• Formal criteria: TC status, codestyle, mandatory documentation. Also make sure to complete the following:
  - There is a single JIRA ticket related to the pull request.
  - The web-link to the pull request is attached to the JIRA ticket.
  - The JIRA ticket has the Patch Available state.
  - The description of the JIRA ticket explains WHAT was made, WHY and HOW.
  - The pull request title is treated as the final commit message. The following pattern must be used: IGNITE-XXXX Change summary where XXXX - number of JIRA issue.
• Design: new code conforms with the design principles of the components it is added to.
• Patch quality: patch cannot be split into smaller pieces, its size must be reasonable.
• Code quality: code is clean and readable, necessary developer documentation is added if needed.
• Tests code quality: test set covers positive/negative scenarios, happy/edge cases. Tests are effective in terms of execution time and resources.

Notes

• Apache Ignite Coding Guidelines

[Copilot]

Pull request overview

Reverts the earlier Gradle wrapper upgrade (8.6 → 8.14.4) to restore the previous Gradle build tooling and related configuration.

Changes:

• Reverted Gradle wrapper distribution, scripts, and wrapper JAR back to Gradle 8.6.
• Removed pluginManagement resolution mapping that was added for newer Palantir Docker plugin resolution.
• Rolled back the Palantir Docker plugin version and adjusted integration test suite configuration.

Reviewed changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
settings.gradle	Removes additional plugin resolution repositories/mapping introduced for the wrapper bump.
gradlew	Reverts POSIX wrapper script to the prior version used with the 8.6 wrapper.
gradlew.bat	Reverts Windows wrapper script to the prior version used with the 8.6 wrapper.
gradle/wrapper/gradle-wrapper.properties	Points wrapper distribution back to gradle-8.6-all.zip and removes newer wrapper properties.
gradle/wrapper/gradle-wrapper.jar	Replaces the wrapper JAR to match the reverted wrapper setup.
gradle/libs.versions.toml	Rolls back com.palantir.docker plugin version to 0.36.0.
buildscripts/java-integration-test.gradle	Sets the integrationTest suite’s testType to INTEGRATION_TEST.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.