LU-14692 tests: wait for osp in conf-sanity/84

LU-14692 tests: wait for osp in conf-sanity/84

Wait for osp to change the first IDIF SEQ to a
normal SEQ, before using replay_barrier.
Otherwise the SEQ change could get lost and we
will trigger LASSERT during replay.

Change-Id: I32daa49d6329902b84eebb00090ae3cebe4a71b0
Test-Parameters: trivial testlist=conf-sanity env=ONLY=84,ONLY_REPEAT=10
Signed-off-by: Li Dongyang <dongyangli@ddn.com>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/50477
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>