RemovedComponents doesn't work in FixedUpdate

hello

## Bevy version

0.14.2

## What you did

have a system remove a Component in an Update system.
use a RemovedComponents in a FixedUpdate system.

## What went wrong

RemovedComponents.read() doesn't return any entities

## Additional information

it works by just moving the system from FixedUpdate to Update

there has been an issue about events not working in FixedUpdate #7691 fixed in this PR #10077. someone has talked about it in the pr and issue. here is a comment about it in the pr https://github.com/bevyengine/bevy/pull/10077#issuecomment-1826825216.

if making events like RemovedComponents works in FixedUpdate too much of a drawback, i think there should be a clear indication on the docs, and even better, a bevy warning about it, since now it just silently fails.

thanks

Start with the Update and FixedUpdate reproduction described in the issue, focusing on RemovedComponents.read() and the related event behavior discussed in PR #10077 and issue #7691. Done means the behavior is corrected or the limitation is clearly documented and surfaced to users, with the FixedUpdate case covered by an appropriate test if the repository provides one.

Written by the indexing model from the issue text.