suites/rados/cephadm: add still running warning to the ignore list

the ignore list already have OSD_DOWN warning, but not still running
warning that may appear if the osd delay while it shutdown

Fixes: https://tracker.ceph.com/issues/70465
Signed-off-by: Nitzan Mordechai <[email protected]>

Author: NitzanMordhai

qa/suites/orch/cephadm/osds/1-start.yaml

@@ -23,6 +23,7 @@ overrides:
     log-ignorelist:
       - OSD_DOWN
       - CEPHADM_FAILED_DAEMON
+      - but is still running
     conf:
       osd:
         osd shutdown pgref assert: true