Node unable to verify the first certificate error

## Environment

* Operating system (including version): macOS Ventura 13.6.1
* mkcert version (from `mkcert -version`): v1.4.4
* Server (where the certificate is loaded): localhost:3000 (frontend), localhost:8080 (backend)
* Client (e.g. browser, CLI tool, or script): Chrome

## What you did

- I followed the instructions, first doing `mkcert -install`

- Entered `mkcert -cert-file ~/cert.pem -key-file ~/key.pem localhost`

- Here are my options for both frontend and backend Node.js https servers:
```
var options = {
key: fs.readFileSync(process.env.SSL_KEY_FILE),
cert: fs.readFileSync(process.env.SSL_CRT_FILE),
ca: fs.readFileSync(process.env.SSL_CRT_FILE),
};
```
I tried adding the ca property, I found a [post](https://stackoverflow.com/questions/75190513/https-request-unable-to-verify-first-certificate#comment132724399_75190513) mentioning it and then I found an [example](https://nodejs.org/docs/latest/api/tls.html#tlscreateserveroptions-secureconnectionlistener) on how to use ca on node's website.

- Finally added `export NODE_EXTRA_CA_CERTS="$(mkcert -CAROOT)/rootCA.pem"` to both my frontend and backend .env files, according to the [README.md](https://github.com/FiloSottile/mkcert#using-the-root-with-nodejs) and this [Issue](https://github.com/FiloSottile/mkcert/issues/78)

- Also tried changing `export NODE_EXTRA_CA_CERTS="$(mkcert -CAROOT)/rootCA.pem"` to `/Users/blahblahblah/Library/blahblahblah/mkcert/rootCA.pem`

## What went wrong

- The frontend terminal displayed this error:
```
⨯ Internal error: TypeError: fetch failed
at Object.fetch (node:internal/deps/undici/undici:11576:11)
at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
Cause: Error: unable to verify the first certificate
at TLSSocket.onConnectSecure (node:_tls_wrap:1627:34)
at TLSSocket.emit (node:events:514:28)
at TLSSocket._finishInit (node:_tls_wrap:1038:8)
at ssl.onhandshakedone (node:_tls_wrap:824:12)
at TLSWrap.callbackTrampoline (node:internal/async_hooks:130:17) {
code: 'UNABLE_TO_VERIFY_LEAF_SIGNATURE'
}
⨯ Internal error: TypeError: fetch failed
at Object.fetch (node:internal/deps/undici/undici:11576:11)
at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
digest: "956933652"
```

- The backend terminal displayed no errors.