Fix unable to autoload constant

ee/lib/elastic/metrics_update_service.rb

@@ -4,13 +4,13 @@ module Elastic
   class MetricsUpdateService
     def execute
       incremental_gauge = Gitlab::Metrics.gauge(:global_search_bulk_cron_queue_size, 'Number of incremental database updates waiting to be synchronized to Elasticsearch', {}, :max)
-      incremental_gauge.set({}, Elastic::ProcessBookkeepingService.queue_size)
+      incremental_gauge.set({}, ::Elastic::ProcessBookkeepingService.queue_size)
 
       initial_gauge = Gitlab::Metrics.gauge(:global_search_bulk_cron_initial_queue_size, 'Number of initial database updates waiting to be synchronized to Elasticsearch', {}, :max)
-      initial_gauge.set({}, Elastic::ProcessInitialBookkeepingService.queue_size)
+      initial_gauge.set({}, ::Elastic::ProcessInitialBookkeepingService.queue_size)
 
       awaiting_indexing_gauge = Gitlab::Metrics.gauge(:global_search_awaiting_indexing_queue_size, 'Number of database updates waiting to be synchronized to Elasticsearch while indexing is paused.', {}, :max)
-      awaiting_indexing_gauge.set({}, Elastic::IndexingControlService.queue_size)
+      awaiting_indexing_gauge.set({}, ::Elastic::IndexingControlService.queue_size)
     end
   end
 end