Revert "[BUGFIX] Fix loading order for extensions"

This reverts commit c0779513b431b19413873893bf630aa3de6fc1fc

The patch has two flaws:
 * Easy: packagePathStack also includes package folder which
         is incompatible to the excludedPaths search
 * Nightmare: Upon uninstalling extensions the PackageManager
         fails due to missing packagePathStack information

Change-Id: I27642b3dea7541cb5f7363172edff147d34999d1
Resolves: #59831
Reverts: #59147
Releases: 6.3, 6.2
Reviewed-on: https://review.typo3.org/31098
Reviewed-by: Markus Klein
Tested-by: Markus Klein