[BUGFIX] Installer: Show correct value for boolean options

Resolves: #53963
Releases: 6.2
Change-Id: I0dd51f2d256c153d6b6a1e247d86c69c5cfd7a7b
Reviewed-on: https://review.typo3.org/25681
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring