[TASK] Fix example in urlencode ViewHelper

Releases: main, 12.4, 11.5
Resolves: #101620
Change-Id: I18563030fd382331a1389c500f313e28383901d2
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/80474


Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>