Add ci.opensearch.org/m2/ mirror for plugin resolution (flow-framework)

[shreyah963]

Description

Add ci.opensearch.org/m2/ mirror for plugin resolution (flow-framework)

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 d07be86.

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

Path	Line	Severity	Description
build.gradle	58	high	New Maven repository added to buildscript block: https://ci.opensearch.org/m2/. Per mandatory supply chain rule, all repository additions must be flagged. Maintainers should verify this URL resolves to a trusted, controlled artifact store and is not a shadow path that could serve malicious build plugins.
build.gradle	191	high	New Maven repository added to project dependency resolution block: https://ci.opensearch.org/m2/. Any artifact resolvable via existing repos could be shadowed here if this path is under different access control than the adjacent /maven2/ path on the same host.
settings.gradle	4	high	New Maven repository added to pluginManagement block: https://ci.opensearch.org/m2/. This path controls Gradle plugin resolution, making it a high-value target. Maintainers should confirm this path is intentional, properly access-controlled on ci.opensearch.org, and distinct from the existing /maven2/ path already present.

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 78.57%. Comparing base (a2aa910) to head (d07be86).

Additional details and impacted files

@@             Coverage Diff              @@
##                3.8    #1449      +/-   ##
============================================
+ Coverage     78.52%   78.57%   +0.04%     
  Complexity     1315     1315              
============================================
  Files           106      106              
  Lines          6045     6045              
  Branches        647      647              
============================================
+ Hits           4747     4750       +3     
+ Misses         1008     1004       -4     
- Partials        290      291       +1     

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[peterzhuamazon]

Expected new mirror for gradle plugins.