[htmx 4] `changed` trigger modifier doesn't seem to work in 4.0.0-beta6

The `changed` modifier appears to block the trigger event from being detected.

Example:

```django

When the `changed` modifier is omitted, the POST request is correctly sent after a 250ms delay on keydown. If `changed` is included, then the POST never fires.

Expected behavior: when a keydown event is detected, only fire the POST if the field has changed

Reproduce the issue with the provided form and `hx-trigger="keydown changed delay:250ms"` example in htmx 4.0.0-beta6. Start at the trigger handling for the `changed` modifier and compare it with the working `keydown delay:250ms` behavior. Done means the delayed POST fires only when the field value has changed.

Written by the indexing model from the issue text.