Merge branch 'es_fixes' into 'master'

Uninitialized constant ElasticIndexerWorker::Client

Fixes https://gitlab.com/gitlab-org/gitlab-ee/issues/772

See merge request !554

CHANGELOG-EE

@@ -7,6 +7,7 @@ v 8.10.0 (unreleased)
   - Prevent the author of an MR from being on the approvers list
   - Isolate EE LDAP library code in EE module (Part 1) !511
   - Make Elasticsearch indexer run as an async task
+  - Fix of removing wiki data from index when project is deleted
 
 v.8.9.7 (unreleased)
   - Fix error in admin dashboard when Geo is enabled and current node is nil.

app/workers/elastic_indexer_worker.rb

@@ -46,7 +46,7 @@ class ElasticIndexerWorker
     })
 
     # Remove wiki index
-    Client.delete_by_query({
+    client.delete_by_query({
       index: ProjectWiki.__elasticsearch__.index_name,
       body: {
         query: {