Add ci.opensearch.org/m2/ mirror for plugin resolution (neural-search)

[shreyah963]

Description

Add ci.opensearch.org/m2/ mirror for plugin resolution (neural-search)

Issues Resolved

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

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[github-actions]

PR Code Analyzer ❗

AI-powered 'Code-Diff-Analyzer' found issues on commit 49b5f8b.

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

Path	Line	Severity	Description
build.gradle	37	high	New Maven repository URL 'https://ci.opensearch.org/m2/' added to buildscript repositories. Per mandatory policy, all package registry changes must be flagged. This is a different path (/m2/ vs the existing /maven2/) on the same CI host — verify this is an intentional, authorized mirror and not a misconfiguration or shadow repository that could serve malicious artifacts to the build classpath.
repositories.gradle	9	high	New Maven repository URL 'https://ci.opensearch.org/m2/' added to project dependency repositories. Per mandatory policy, all package registry changes must be flagged. Gradle resolves dependencies from repositories in order; an additional source expands the artifact supply chain attack surface for all project dependencies.
settings.gradle	14	high	New Maven repository URL 'https://ci.opensearch.org/m2/' added to pluginManagement repositories. Per mandatory policy, all package registry changes must be flagged. Plugin management repositories are especially sensitive as Gradle plugins execute arbitrary code during the build; an unauthorized or compromised source here could lead to full build system compromise.

The table above displays the top 10 most important findings.

Total: 3 | Critical: 0 | High: 3 | 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.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.42%. Comparing base (2ea9445) to head (49b5f8b).

Additional details and impacted files

@@             Coverage Diff              @@
##                3.8    #1920      +/-   ##
============================================
- Coverage     83.42%   83.42%   -0.01%     
+ Complexity     3897     3895       -2     
============================================
  Files           291      291              
  Lines         13844    13844              
  Branches       2304     2304              
============================================
- Hits          11550    11549       -1     
  Misses         1458     1458              
- Partials        836      837       +1     

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[peterzhuamazon]

Expected new mirror for gradle plugins.