New terraform feature: Override GRQ ILM expiration time, needed for PST in particular

[philipjyoon]

Checked for duplicates

Yes - I've already checked

Alternatives considered

Yes - and alternatives don't suffice

Related problems

No response

Describe the feature request

Create a terraform variable named something like grq_ilm_exp_days and use that to override ilm expiration days for GRQ ES. This is needed for PST at this time.

Relevant curl command:

curl -X PUT "http://localhost:9200/_ilm/policy/opera_grq_ilm_policy" -H "Content-Type: application/json" -d '{
  "policy": {
    "phases": {
      "delete": {
        "min_age": "150d",
        "actions": {
          "delete": {
            "delete_searchable_snapshot": true
          }
        }
      }
    }
  }
}'

GRQ ES ILM policy is hard-coded here:
https://github.com/nasa/opera-sds-pcm/blob/develop/conf/sds/files/elasticsearch/es_ilm_policy_grq.json