If TYPO3_PATH_ROOT environment variable is set
before executing functional tests, we need to make
sure that we re-set it to the path of the test system
because the TYPO3 bootstrap since version 8 evaluates
this variable and PATH_site of the tests system would
point to the original root instead of the test system root.
Also evaluate TYPO3_PATH_ROOT as document root for unit tests
If TYPO3_PATH_ROOT environment variable is set before executing functional tests, we need to make sure that we re-set it to the path of the test system because the TYPO3 bootstrap since version 8 evaluates this variable and PATH_site of the tests system would point to the original root instead of the test system root.
Also evaluate TYPO3_PATH_ROOT as document root for unit tests