Add ci.opensearch.org/m2/ mirror for plugin resolution (geospatial)

[shreyah963]

Description

Add ci.opensearch.org/m2/ mirror for plugin resolution (geospatial)

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 23aea8a.

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

Path	Line	Severity	Description
build.gradle	31	high	New Maven repository source added (https://ci.opensearch.org/m2/) in buildscript block. Per mandatory policy, all package registry URL additions must be flagged regardless of apparent legitimacy. Maintainers must verify this URL resolves to the intended artifact store and cannot be hijacked.
build.gradle	111	high	New Maven repository source added (https://ci.opensearch.org/m2/) in allprojects repositories block. Same URL as above but in a separate resolution context; must be independently verified.
client/build.gradle	23	high	New Maven repository source added (https://ci.opensearch.org/m2/) to client subproject. Artifacts resolved from this repo for the client module must be verified as originating from the intended OpenSearch CI infrastructure.
libs/h3/build.gradle	33	high	New Maven repository source added (https://ci.opensearch.org/m2/) to the h3 library subproject. Artifacts resolved from this repo for the h3 module must be verified as originating from the intended OpenSearch CI infrastructure.
settings.gradle	12	high	New Maven repository source added (https://ci.opensearch.org/m2/) to the pluginManagement block. This is particularly sensitive as it controls resolution of Gradle plugins themselves, not just project dependencies — a compromised artifact here could execute arbitrary code during the build.

The table above displays the top 10 most important findings.

Total: 5 | Critical: 0 | High: 5 | Medium: 0 | Low: 0

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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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