fix: Node.replaceWith does not throw w/o parent (#1969)

* fix: Node.replaceWith does not throw w/o parent

```js
let div = document.createElement("div");
let span = document.createElement("span");

div.parentNode; // null
span.parentNode; // null

div.replaceWith(span); // ok
```

* chore: remove unused DOMException import

* chore: [#0] Adds unit test

---------

Co-authored-by: David Ortner <david@ortner.se>

Author: lukeed

packages/happy-dom/src/nodes/child-node/ChildNodeUtility.ts

@@ -1,4 +1,3 @@
-import DOMException from '../../exception/DOMException.js';
 import * as PropertySymbol from '../../PropertySymbol.js';
 import Node from '../node/Node.js';
 import type IParentNode from '../parent-node/IParentNode.js';
@@ -29,7 +28,7 @@ export default class ChildNodeUtility {
 		const parent = <IParentNode>childNode[PropertySymbol.parentNode];
 
 		if (!parent) {
-			throw new DOMException('This element has no parent node.');
+			return;
 		}
 
 		for (const node of nodes) {

packages/happy-dom/test/nodes/element/Element.test.ts

@@ -1203,6 +1203,10 @@ describe('Element', () => {
 			element.replaceWith(node1, node2);
 			expect(isCalled).toBe(true);
 		});
+
+		it('Should not throw when there is no parent node.', () => {
+			document.createElement('div').replaceWith(document.createElement('div'));
+		});
 	});
 
 	describe('before()', () => {