Update the developer guide to add Gradle Check Metrics Dashboard deta…

…ils (opensearch-project#13919)

Signed-off-by: Prudhvi Godithi <pgodithi@amazon.com>

DEVELOPER_GUIDE.md

@@ -62,6 +62,7 @@
  - [LineLint](#linelint)
  - [Lucene Snapshots](#lucene-snapshots)
  - [Flaky Tests](#flaky-tests)
+ - [Gradle Check Metrics Dashboard](#gradle-check-metrics-dashboard)
 
 # Developer Guide
 
@@ -660,3 +661,7 @@ If you encounter a build/test failure in CI that is unrelated to the change in y
 4. If an existing issue is found, paste a link to the known issue in a comment to your PR.
 5. If no existing issue is found, open one.
 6. Retry CI via the GitHub UX or by pushing an update to your PR.
+
+### Gradle Check Metrics Dashboard
+
+To get the comprehensive insights and analysis of the Gradle Check test failures, visit the [OpenSearch Gradle Check Metrics Dashboard](https://metrics.opensearch.org/_dashboards/app/dashboards#/view/e5e64d40-ed31-11ee-be99-69d1dbc75083). This dashboard is part of the [OpenSearch Metrics Project](https://github.com/opensearch-project/opensearch-metrics) initiative. The dashboard contains multiple data points that can help investigate and resolve flaky failures. Additionally, this dashboard can be used to drill down, slice, and dice the data using multiple supported filters, which further aids in troubleshooting and resolving issues.