Statefulset metadata Annotations removed by operator

[oliveagle]

Bug Report

What did you do?

Create a ElasticSearch cluster with 3 nodes. add some annotations in sts metadata. then scale up the cluster. Annotation we added in sts metadata disappered.

Add arbitrary annotations in sts metadata

Do these following operations. they all will remove annotations in sts metadata

• scale up/down
• replace image version of ElasticSearch

What did you expect to see?

We need those annotations to be persistent.(operator don't clean customized annotations in sts metadata).

Environment

• ECK version:

  version: 1.1.1
  hash: b6f69fc

We added 3 line of code that solve this problem. Here are the changes.

[sebgl]

Related: #2652 to include the sset annotations in the Elasticsearch resource