feat(elasticsearch): Add endpoint for getting the size of timeseries indices

[iprentic]

Example output against quickstart:

curl -i -X POST http://localhost:8080/operations\?action\=getIndexSizes | tail -n1 | jq

{
  "value": {
    "indexSizes": [
      {
        "aspectName": "datahubingestionrunsummary",
        "sizeMb": 0.208,
        "indexName": "datajob_datahubingestionrunsummaryaspect_v1",
        "entityName": "datajob"
      },
      {
        "aspectName": "dashboardusagestatistics",
        "sizeMb": 0.208,
        "indexName": "dashboard_dashboardusagestatisticsaspect_v1",
        "entityName": "dashboard"
      },
      {
        "aspectName": "chartusagestatistics",
        "sizeMb": 0.208,
        "indexName": "chart_chartusagestatisticsaspect_v1",
        "entityName": "chart"
      },
      {
        "aspectName": "datasetprofile",
        "sizeMb": 0.208,
        "indexName": "dataset_datasetprofileaspect_v1",
        "entityName": "dataset"
      },
      {
        "aspectName": "datahubingestioncheckpoint",
        "sizeMb": 0.208,
        "indexName": "datajob_datahubingestioncheckpointaspect_v1",
        "entityName": "datajob"
      },
      {
        "aspectName": "assertionrunevent",
        "sizeMb": 0.208,
        "indexName": "assertion_assertionruneventaspect_v1",
        "entityName": "assertion"
      },
      {
        "aspectName": "dataprocessinstancerunevent",
        "sizeMb": 0.208,
        "indexName": "dataprocessinstance_dataprocessinstanceruneventaspect_v1",
        "entityName": "dataprocessinstance"
      },
      {
        "aspectName": "operation",
        "sizeMb": 0.208,
        "indexName": "dataset_operationaspect_v1",
        "entityName": "dataset"
      },
      {
        "aspectName": "datasetusagestatistics",
        "sizeMb": 0.208,
        "indexName": "dataset_datasetusagestatisticsaspect_v1",
        "entityName": "dataset"
      }
    ]
  }
}

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable). If a new feature has been added a Usage Guide has been added for the same.
• For any breaking change/potential downtime/deprecation/big changes an entry has been made in Updating DataHub

[RyanHolstien]

Are we only interested in TimeSeries? I think for the operational endpoint it would be useful to support both. Maybe TimeSeries is enough for just the MVP though.

[iprentic]

This endpoint is specifically for timeseries indices, yes