Bug: Pasting text from the clipboard into a CustomElementNode does not work properly

If you define a CustomElementNode class with isInline(): true and/or canBeEmpty(): true, then no text can be inserted from the clipboard. In this case, the text is inserted after the CustomElementNode. The same applies to adding DecoratorNodes. I assume that no nodes of any kind can be added to the CustomElementNode as a child.
But if isInline():false and canBeEmpty():false, then it works as expected.

Lexical version: 0.16.1

Link to code example:
https://stackblitz.com/edit/vitejs-vite-qmtgsj

## The current behavior
After inserting text from the clipboard (or adding a new node, such as a DecoratorNode) into the CustomElementNode, the text appears after the CustomElementNode

## The expected behavior
Text from clipboard (or new DecoratorNode) should added at current cursor position

## Impact of fix
HIGH
It affects all classes that extend from ElementNode and that may not be empty or are inline elements.