Add ci.opensearch.org/m2/ mirror to buildscript and project repos (security-analytics)

[peterzhuamazon]

Description

Add ci.opensearch.org/m2/ mirror to buildscript and project repos (security-analytics)

Issues Resolved

opensearch-project/opensearch-build#6278 (comment)

[github-actions]

PR Code Analyzer ❗

AI-powered 'Code-Diff-Analyzer' found issues on commit ec03a83.

⛔ Hard block: Issues at High severity or above will block this PR from merging.

Path	Line	Severity	Description
build.gradle	53	high	New Maven repository URL 'https://ci.opensearch.org/m2/' added to buildscript repositories. This is a package source change that must be verified — artifacts resolved from this endpoint could be substituted or tampered with, and the path '/m2/' differs from the existing '/maven2/' endpoint whose legitimacy was previously established.
build.gradle	186	high	New Maven repository URL 'https://ci.opensearch.org/m2/' added to publishing repositories. Same unverified endpoint added to the publishing block, which controls where build artifacts are deployed. Adding an unverified repository to the publishing configuration could redirect artifact uploads to an unintended or attacker-controlled location.

The table above displays the top 10 most important findings.

Total: 2 | Critical: 0 | High: 2 | 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.

[peterzhuamazon]

expected mirror update.