LU-17670 tests: sanity-flr/33b allow bigger time difference

LU-17670 tests: sanity-flr/33b allow bigger time difference

Allow a bigger time difference between read that switching among
mirrors.

Test-Parameters: trivial testlist=sanity-flr env=ONLY=33b
Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: I14482e290fe5a96d1d10b2d47c8b4cfcadec96ec
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/56752
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Colin Faber <cfaber@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>