version bump: 3.8.0

[Swiddis]

Description

[Describe what this change achieves]

Related Issues

Resolves #[Issue number to be closed when this PR is merged]

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
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[github-actions]

PR Code Analyzer ❗

AI-powered 'Code-Diff-Analyzer' found issues on commit 422be4f.

Path	Line	Severity	Description
build.gradle	14	high	Dependency version change: opensearch_version bumped from 3.7.0-SNAPSHOT to 3.8.0-SNAPSHOT. Per mandatory policy, all dependency version changes must be flagged for maintainer verification regardless of apparent legitimacy. SNAPSHOT versions are particularly risky as they resolve to mutable, non-pinned artifacts that could be substituted with malicious builds.

The table above displays the top 10 most important findings.

Total: 1 | Critical: 0 | High: 1 | Medium: 0 | Low: 0

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Pull Requests Author(s): Please update your Pull Request according to the report above.

Repository Maintainer(s): You can bypass diff analyzer by adding label skip-diff-analyzer after reviewing the changes carefully, then re-run failed actions. To re-enable the analyzer, remove the label, then re-run all actions.

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⚠️ Note: The Code-Diff-Analyzer helps protect against potentially harmful code patterns. Please ensure you have thoroughly reviewed the changes beforehand.

Thanks.

[RyanL1997]

relate to: opensearch-project/sql#5498