[BUGFIX] Fix tests according to changes in #57199

Unit tests have been forgotten to be adapted,
so fix them now to make travis happy again.

Also remove the superfluous constructor
in InstallUtility, as both dependencies
are injected anyway.

Resolves: #57247
Related: #57199
Releases: 6.2
Change-Id: I40c39705c2db546b38d94936feac2c8757eed8da
Reviewed-on: https://review.typo3.org/28722
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel