[BUGFIX] Defer requests to LiveSearch

The LiveSearch in the TYPO3 backend is configured to wait 250ms for
additional input before sending the request to the server. Previously,
every entered character triggered an independent search, unnecessarily
hammering the server with requests.

Resolves: #100011
Releases: 11.5, 10.4
Change-Id: Ifd2499b03ed6f149432f0224480a188a35ef7c88
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/77926


Tested-by: core-ci <typo3@b13.com>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>