Elasticsearch validating webhook swallows errors

[pebrc]

https://github.com/elastic/cloud-on-k8s/blob/49dc892dacd9d3f83c95a111812506485c3bf319/pkg/controller/elasticsearch/validation/validations.go#L189-L190

The error returned from UnpackConfig is swallowed. We should at least log it is not return it to the user.

https://github.com/elastic/cloud-on-k8s/blob/49dc892dacd9d3f83c95a111812506485c3bf319/pkg/controller/elasticsearch/validation/validations.go#L212-L214

is triggered incorrectly if UnpackConfig fails and the validations haven't even run.

Example test case:

  - name: default
    config:
      node.roles: ["master", "data", "ingest", "ml"]
      cluster.max_shards_per_node: "2000"
      cluster.max_shards_per_node.frozen: "4000"

This is theoretically correct Elasticsearch configuration but impossible to express in valid YAML