GH-39170: [Java] Improve error message explaining why TestTls might fail

[jbonofre]

Rationale for this change

What changes are included in this PR?

Are these changes tested?

Are there any user-facing changes?

• Closes: [Java] Improve error message when Flight Core TestTls fails #39170

[github-actions]

Thanks for opening a pull request!

If this is not a minor PR. Could you open an issue for this pull request on GitHub? https://github.com/apache/arrow/issues/new/choose

Opening GitHub issues ahead of time contributes to the Openness of the Apache Arrow project.

Then could you also rename the pull request title in the following format?

GH-${GITHUB_ISSUE_ID}: [${COMPONENT}] ${SUMMARY}

or

MINOR: [${COMPONENT}] ${SUMMARY}

In the case of PARQUET issues on JIRA the title also supports:

PARQUET-${JIRA_ISSUE_ID}: [${COMPONENT}] ${SUMMARY}

See also:

• Other pull requests
• Contribution Guidelines - How to contribute patches

[jbonofre]

This closes #39170

[github-actions]

⚠️ GitHub issue #39170 has been automatically assigned in GitHub to PR creator.

[lidavidm]

Thanks!

[jbonofre]

@lidavidm I updated the PR according to your suggestion. Thanks again. This PR is the first one of several coming from me 😄

[conbench-apache-arrow]

After merging your PR, Conbench analyzed the 5 benchmarking runs that have been run so far on merge-commit 7ba0228.

There were no benchmark performance regressions. 🎉

The full Conbench report has more details. It also includes information about 4 possible false positives for unstable benchmarks that are known to sometimes produce them.