[TASK] Improve wording in Install Tool

[TASK] Improve wording in Install Tool

- Fix typos
- Remove outdated text
- Wrap code into <code> tags

Resolves: #80563
Releases: master
Change-Id: Idfb65c294aaf62198d5581a89ab03b3678ab7ee1
Reviewed-on: https://review.typo3.org/52253
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Thomas Hohn <thomas@hohn.dk>
Tested-by: Thomas Hohn <thomas@hohn.dk>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>