Add UBI to the list and update gitignores (#254)

Signed-off-by: Sayali Gaikawad <gaiksaya@amazon.com>

Author: gaiksaya

dashboards-plugins/.gitignore

@@ -13,4 +13,4 @@ securityAnalyticsDashboards/
 mlCommonsDashboards/
 assistantDashboards/
 flowFrameworkDashboards/
-queryInsightsDashboards//
+queryInsightsDashboards/

plugins/.gitignore

@@ -26,3 +26,5 @@
 /query-insights/
 /dashboards-investigation/
 /opensearch-prometheus-exporter/
+/user-behavior-insights/
+/search-relevance/

plugins/.meta

@@ -28,6 +28,7 @@
     "query-insights": "git@github.com:opensearch-project/query-insights.git",
     "search-relevance": "git@github.com:opensearch-project/search-relevance.git",
     "dashboards-investigation": "git@github.com:opensearch-project/dashboards-investigation.git",
-    "opensearch-prometheus-exporter": "git@github.com:opensearch-project/opensearch-prometheus-exporter"
+    "opensearch-prometheus-exporter": "git@github.com:opensearch-project/opensearch-prometheus-exporter",
+    "user-behavior-insights": "git@github.com:opensearch-project/user-behavior-insights.git"
   }
-}
+}