ZTS: Remove zfs_allow_010_pos expection for FreeBSD

This issue should now be address by PR #15376 and the exception
for this test case be removed.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Umer Saleem <usaleem@ixsystems.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #15382