qa: ignore cluster warning (evicting unresponsive ...) with tasks/mgr-osd-full

fs/full/subvolume_ls.sh will restart ceph-mgr periodically and
that does not cleanup libcephfs handles.

Fixes: http://tracker.ceph.com/issues/73278
Signed-off-by: Venky Shankar <[email protected]>

Author: vshankar

qa/suites/fs/full/tasks/mgr-osd-full.yaml

@@ -1,5 +1,7 @@
 overrides:
   ceph:
+    log-ignorelist:
+      - evicting unresponsive client
     conf:
       global:
         osd_pool_default_size: 1