Merge branch '10420-use-best-compression' into 'master'

elasticsearch: Switch from LZ4 to DEFLATE compression

Closes #10420

See merge request gitlab-org/gitlab-ee!10072

ee/app/models/concerns/elastic/application_search.rb

@@ -13,6 +13,7 @@ module Elastic
 
       settings \
         index: {
+          codec: 'best_compression',
           analysis: {
             analyzer: {
               default: {

ee/changelogs/unreleased/10420-use-best-compression.yml

+---
+title: 'elasticsearch: Switch from LZ4 to DEFLATE compression'
+merge_request: 10072
+author:
+type: changed