[QA][Code Coverage] Merging failing

[wayneseymour]

The code coverage ingestion system has been receiving "empty" coverage summary files for over a month.

Empty Example:

{
  "total": {
    "lines": {
      "total": 0,
      "covered": 0,
      "skipped": 0,
      "pct": "Unknown"
    },
    "statements": {
      "total": 0,
      "covered": 0,
      "skipped": 0,
      "pct": "Unknown"
    },
    "functions": {
      "total": 0,
      "covered": 0,
      "skipped": 0,
      "pct": "Unknown"
    },
    "branches": {
      "total": 0,
      "covered": 0,
      "skipped": 0,
      "pct": "Unknown"
    },
    "branchesTrue": {
      "total": 0,
      "covered": 0,
      "skipped": 0,
      "pct": "Unknown"
    }
  }
}

[elasticmachine]

Pinging @elastic/kibana-qa (Team:QA)