EX-7752 test: hot-pools test_59: not expected flag 'stale'

EX-7752 test: hot-pools test_59: not expected flag 'stale'

Make the 1st mirror preferable for write for the test purpose.

Test-Parameters: trivial env=ONLY=59 testlist=hot-pools
Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: I06c33badfc10ff9743df83a6e421e27afc9b6dbd
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/51502
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Colin Faber <cfaber@ddn.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>