`data` argument of `createTextNode` is not coerced into a string

Describe the bug

Hello! I'm filing this issue in response to an issue that got raised over at https://github.com/testing-library/svelte-testing-library/issues/343.

document.createTextNode(data) is used to create text nodes
The input data is expected to be a DOMString
In browsers I've tested (latest Chromium, Firefox, and Safari), if you pass a non-string to createTextNode, it will be coerced into a string
In Happy DOM, the data is not coerced, and node.data ends up not a string, causing problems in downstream consumers

To Reproduce

// index.js
import { Window } from "happy-dom";

const window = new Window({ url: "https://localhost:8080" });
const node = window.document.createTextNode(2);

console.log(node.data, typeof node.data);

> node index.js
2 number

In the case of the issue filed in @testing-library/svelte: svelte@4 erroneously passes a non-string to createTextNode, and then the pretty printing library that is used to print test results chokes because it tries to do a String.replace on node.data, which may not be a string

Expected behavior

I expect the resulting data property of createTextNode to always be a string

Additional context

Tested with happy-dom@14.4.0

capricorn86 / happy-dom

`data` argument of `createTextNode` is not coerced into a string #1380