I tried to mock a CORS request and it didn't work.\
The mock appears as called but the `fetch` in the web code is not resolving.

Here is a piece of code that reproduces the issue:

```js
const Wendigo = require('wendigo');

const MAIN_ORIGIN = 'http://example.com'
const MAIN_URL = `${MAIN_ORIGIN}/hello`;
const FETCH_URL = 'http://otherexample.com/eehehhehe';

let browser;

async function test() {
browser = await Wendigo.createBrowser();
browser.requests.mock(MAIN_URL, {
body: `


(function(){
fetch("${FETCH_URL}")
.then(() => (document.getElementById('the-id').innerHTML = 'HOORAYYYY'))
})();

HEYYYY

ITZ A SAZ DAY :(

`,
});

const mock = browser.requests.mock(FETCH_URL, {
body: 'hihihihihiihhi',
headers: {
'Access-Control-Allow-Headers ': 'authorization,content-type',
'Access-Control-Allow-Methods': 'PATCH,GET,OPTIONS,POST,PUT',
'Access-Control-Allow-Origin': MAIN_ORIGIN,
'Access-Contro-Allow-Credentials': 'true',
},
});

await browser.wait();
await browser.open(MAIN_URL);
await browser.waitForText('HEYYYY', 5000); // This works
await mock.assert.called(); // This works
await browser.waitForText('HOORAYYYY', 5000); // This doesn't
}

test().finally(() => browser.close());
```