Failed to execute 'insertBefore' on 'Node': This node type does not support this method

I get the `DOMException: Failed to execute 'insertBefore' on 'Node': This node type does not support this method.` in [child-list.ts:57](https://github.com/ampproject/worker-dom/blob/main/src/main-thread/commands/child-list.ts#L57): `target.insertBefore(newNode, (nextSibling && getNode(nextSibling)) || null);`. The `target` and `newNode` are text nodes (`nodeName === "#text"`) and `nextSibling` is undefined. You cannot add children to a text node.
Could you please fix it by checking `if (target.nodeType !== 3)`?

Stacktrace:
> Uncaught DOMException: Failed to execute 'insertBefore' on 'Node': This node type does not support this method.
> at workerdom.min.js:2:7552
> at Uint16Array.forEach ()
> at Object.execute (workerdom.min.js:2:7505)
> at workerdom.min.js:2:10802
> at Array.forEach ()
> at syncFlush (workerdom.min.js:2:10604)

I am calling `el.innerHTML = "..."` in a loop.

Start with src/main-thread/commands/child-list.ts at line 57, where insertBefore is called with the reported text-node target. Reproduce the failure using an innerHTML loop and verify that the resulting behavior no longer raises the DOMException for text-node targets.

Written by the indexing model from the issue text.