Add ci.opensearch.org/m2/ mirror to buildscript and project repos (sql)

[peterzhuamazon]

Description

Add ci.opensearch.org/m2/ mirror to buildscript and project repos (sql)

Issues Resolved

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

[github-actions]

PR Code Analyzer ❗

AI-powered 'Code-Diff-Analyzer' found issues on commit 8a16fa7.

Path	Line	Severity	Description
build.gradle	71	high	A new Maven repository URL (https://ci.opensearch.org/m2/) is added in three build contexts (buildscript, project, and subprojects). While the domain matches existing trusted repos, the path /m2/ differs from the existing /maven2/ and snapshot paths already present. Per mandatory policy, all new package registry sources must be flagged regardless of apparent legitimacy — maintainers should verify this endpoint is an officially sanctioned OpenSearch artifact mirror and not a path that could serve attacker-controlled artifacts.

The table above displays the top 10 most important findings.

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

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