Elastic Cloud on Kubernetes version 1.4.0

[Helm] Support additional environment variables #4181
Add support for a user-defined transport CA certificate and key #4053 (issue: #2812)
Add support for DaemonSetUpdateStrategy #4049 (issue: #3839)
[Helm] Use ValidatingWebhookConfiguration v1 on supported Kubernetes versions #3963 (issues: #3886, #3958)
Include Beats daemonsets in the diagnostic bundle #3908
Add support for webhook constraints #3876 (issue: #3431)
Remove unnecessary metrics from _nodes ES API request #3860 (issue: #3249)
Allow automatic Elasticsearch nodes discovery #3837 (issues: #3182, #3723)
Enable webhook dry run on supported Kubernetes versions #3834 (issue: #1233)
Create one transport certificates Secret per StatefulSet #3828 (issue: #3734)

Update client-go to 0.18.14 #4097 (issue: #4087)
Don’t duplicate user-provided Enterprise Search encryption keys when reusing them #4052 (issue: #4051)
Add a replacement mechanism to work around nil handling in ucfg #4041 (issue: #3718)
Avoid touching root filesystem in Kibana init script #4023 (issue: #4022)
Don’t allow downscales if some shards are unassigned #3883 (issue: #3867)
Include secret token in APM Server config checksum #3858 (issue: #523)
Do not set the default elasticsearch-data volume if claims are provided in the Elasticsearch manifest #3806 (issue: #2574)