LU-15996 quota: change 'none' to 'expired' for grace

LU-15996 quota: change 'none' to 'expired' for grace

If the grace time is expired, the output of grace in 'lfs quota'
is better to use 'expired' than 'none'.

Test-Parameters: trivial testlist=sanity-quota
Signed-off-by: Honghao Zhang <hongchao@whamcloud.com>
Change-Id: I7a3fac77ca6e16ad406bef0bd7642d6d50feb4b2
Reviewed-on: https://review.whamcloud.com/47912
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Sergey Cheremencev <sergey.cheremencev@hpe.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>