(#19236) Uninstaller: Verify homedirs are removed when is_purge is true

This commit adds /var/lib/peadmin, the peadmin user homedir, to the list of
directories to verify are gone after the uninstaller completes.
Merge pull request #386 from haus/ticket/19236_verify_homedir_removal

(#19236) PE-Uninstaller: Verify homedirs are removed when is_purge is true