PR checks failing as testng-7.2.0.jar no longer exists on repo.jenkins-ci.org

[sxa]

The Groovy checks on PRs are failing as they can no longer download test-ng 7.2.0 from jenkins-ci.org.
Passing log: https://github.com/adoptium/ci-jenkins-pipelines/actions/runs/7213899246/job/19654797971?pr=836 (Seemed to pull correctly: Downloading https://repo.jenkins-ci.org/public/org/testng/testng/7.2.0/testng-7.2.0.jar to /tmp/gradle_download7089325946772859694bin
Failing log: https://github.com/adoptium/ci-jenkins-pipelines/actions/runs/7213899246/job/19863065107

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':test'.
> Could not resolve all files for configuration ':testRuntimeClasspath'.
   > Could not find org.testng:testng:7.2.0.
     Searched in the following locations:
       - https://repo.maven.apache.org/maven2/org/testng/testng/7.2.0/testng-7.2.0.pom
       - https://repo.jenkins-ci.org/releases/org/testng/testng/7.2.0/testng-7.2.0.pom
       - https://repo.jenkins-ci.org/public/org/testng/testng/7.2.0/testng-7.2.0.pom
     Required by:
         project : > org.codehaus.groovy:groovy-all:3.0.4 > org.codehaus.groovy:groovy-testng:3.0.4

* Try:
Run with --stacktrace option to get the stack trace. Run with --debug option to get more log output. Run with --scan to get full insights.

Found as part of #864 (comment) and ignored for the purposes of merging that PR.

[karianna]

#871 fixes this