ReferenceError: cov_2a33nrkdo3 is not defined

```
console.error
ReferenceError: cov_2a33nrkdo3 is not defined
at parseArgs (eval at (/Users/leonardorick/Documents/git/others/utils/javascript/node_modules/jsdom-worker/src/index.js:130:6), :9:3)
at Object.eval (eval at (/Users/leonardorick/Documents/git/others/utils/javascript/node_modules/jsdom-worker/src/index.js:130:6), :6:23)
at /Users/leonardorick/Documents/git/others/utils/javascript/node_modules/jsdom-worker/src/index.js:139:2
```

to reproduce you can go to [my repo](https://github.com/LeonardoRick/utils/blob/main/javascript/src/run-on-worker.js) and run the tests as

```
npm run test -- --coverage
```

The error only appear when I try to run the tests with coverage enabled and it looks really like an internal thing breaking that I couldn't understand the relation with the coverage flag

Reproduce the failure from the linked run-on-worker.js example with `npm run test -- --coverage`, then inspect the worker evaluation path around node_modules/jsdom-worker/src/index.js:130-139. Compare the covered and non-covered runs to identify why the generated coverage reference is unavailable inside the worker; done means the coverage run completes without this ReferenceError.

索引モデルが issue の本文から書いたものです。