[TASK] Stabilize ImportCest.php acceptance test

Sometimes during testing the imported page
404 can't be found.

The import acceptance test has been improved
using the given "getPageXPathByPageName" method
so it will hopefully behave in the future.

Resolves: #95116
Releases: master
Change-Id: Ic37d5afa014ee1c823b34f1a3700338d78c8a3b9
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/70912


Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Benni Mack <benni@typo3.org>