LU-16187 tests: Fix is_project_quota_supported()

LU-16187 tests: Fix is_project_quota_supported()

is_project_quota_supported() is called from sanity-quota.sh
to verify if the ldiskfs FS $ENABLE_PROJECT_QUOTAS is true
and to verify if current version of lfs command supports
'project'.  To do this it calls 'lfs --help' which is
not supported. This patch moves 'lfs --help' call to
'lfs --list-commands' call to verfiy if the present
version of lfs supports 'project'

Test-Parameters: trivial testlist=sanity-quota
Signed-off-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Change-Id: Iba7e6696d3fa9e980088f448ae72b07a4b47f4f2
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/48654
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Hongchao Zhang <hongchao@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>