Layout Grid: Rerender is closing the inline Inserter

This was discovered after the recent Gutenberg v14.2.0 upgrade (p1664214321796799/1664214321.580149-slack-CBTN58FTJ). Fortunately, it shouldn't affect many users because it requires a ⚡ fast click on the `+` button right after selecting the columns count. Such a speed is not an issue for the testing framework, though (Playwright), so for now, we needed to [manually pause the execution](https://github.com/Automattic/wp-calypso/blob/ed1ef6ad7c5c00cdee754d17bae854a13be943b0/packages/calypso-e2e/src/lib/blocks/block-flows/layout-grid.ts#L54-L61) to make the test pass, as there's nothing else we can hook on to (like an "is-loading" class or attribute change).

I'm attaching a repro video so it's clear what the bug looks like:

https://user-images.githubusercontent.com/1451471/194037156-29b76694-cc39-46de-aa98-a4aacfeec7f4.mov

/cc @fullofcaffeine @worldomonation