qa/*/osd-markdown.sh: propagate map to osd before testing its reaction

qa/*/osd-markdown.sh: propagate map to osd before testing its reaction

Mon might fail to share the newest map with any of up osds, e.g.,
due to an injected broken pipe. Since we don't have any client
activities during the osd-markdown tests, osds might be unaware of
the map changes made through CLI. Make sure osds have pulled the
newest map down before we can test its reaction correctly.

Fixes: https://tracker.ceph.com/issues/44662
Signed-off-by: xie xingguo <xie.xingguo@zte.com.cn>