Bug: Select all (cmd/ctrl + A) doesn't work when there's a DecoratorBlockNode with nested editors as the first child

https://user-images.githubusercontent.com/688415/233078980-ae2554ef-d72a-47d3-9852-b0d4dc571921.mov

Lexical version: 0.10.0 (if this is what's running on playground.lexical.dev right now)

This could be related to #4357, although in this case the select all keyboard shortcut doesn't select any text at all.

## Steps To Reproduce

1. Insert an experimental table node
2. Remove any content above it
3. Try to select everything with cmd/ctrl + A (as seen attempted in the Keyboard window in the video recording above)

## The current behavior
The select all keyboard shortcut does nothing (or technically speaking, it seems to be selecting everything and deselecting again right after)

## The expected behavior
The select all keyboard shortcut should select everything in the editor.