coverage-final.json has an unnecessary data property for some files, which is breaking merge.
{"C:\Code\app\src\App.js": {"data":{"path":"C:\Code\app\src\App.js","statementMap": {}}, ,"C:\Code\app\src\index.js": {"data":{"path":"C:\Code\app\src\index.js","statementMap"{}, ,"C:\Code\app\src\components\logo\Logo.tsx": {"path":"C:\Code\app\src\components\logo\Logo.tsx","statementMap":{}},