[TASK] Remove redundancies in install tool ext conf template

This patch:

1. Removes a redundant usage of a "NoSpace" VH and
   the associated namespace import since there are no
   other usages.
2. Deletes the VH class since it is not used elsewhere.
3. Removes an always-true and therefore redundant "if"

Releases: master
Resolves: #89956
Change-Id: I943653e04fa731cdc4bdcbc8d6e32663e3ca30c9
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/62648


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Jan Stockfisch <typo3@jan-stockfisch.de>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Jan Stockfisch <typo3@jan-stockfisch.de>
Reviewed-by: Benni Mack <benni@typo3.org>