[FOLLOWUP][BUGFIX] Fix parse time calculation

Unit test: Fix namespace, test file location and class inheritance.

Change-Id: Ida24b5adf747dc7c259a966fcddfdb7feb9f0951
Resolves: #80742
Releases: master, 8.7
Reviewed-on: https://review.typo3.org/52827


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>