[TASK] Improve a11y of disabled recycler search-submit-button

This changes the `disabled`-attribute of the
recycler's search-submit-button. Thereby screen-
readers can announce that the button is disabled.

Before this there was toggling implemented for
`class="disabled"`. Thereby the 'disabled' button
was still active and could be activated by
keyboard.

Resolves: #104817
Releases: main
Change-Id: Ifb99481624c5cc24f590c7e9d0f3a61ab9f997aa
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/85870


Reviewed-by: Andreas Nedbal <andy@pixelde.su>
Tested-by: Benjamin Kott <benjamin.kott@outlook.com>
Reviewed-by: Benjamin Kott <benjamin.kott@outlook.com>
Tested-by: Andreas Nedbal <andy@pixelde.su>