LU-18690 tests: sanity-quota/79 should return 0

LU-18690 tests: sanity-quota/79 should return 0

the test should not return a result of background process trying
to access pool's information.

Test-Parameters: trivial
Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Change-Id: Ib9446b222c3be721e9ec5e9a4da67f249ac46aa0
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/57947
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Sergey Cheremencev <scherementsev@ddn.com>
Reviewed-by: Lai Siyao <lai.siyao@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>