qa/cephfs: add MDS_CLIENTS_BROKEN_ROOTSQUASH to ignorelist

MDS_CLIENTS_BROKEN_ROOTSQUASH is generated and expected by
test_rootsquash_nofeature but it hasn't be added to ignorelist as a
result of which QA code marks the job as failed even though all tests
finished running successfully.

Introduced-by: bccc8ce
Fixes: https://tracker.ceph.com/issues/66075
Signed-off-by: Rishabh Dave <[email protected]>

Author: rishabh-d-dave

qa/suites/fs/functional/tasks/admin.yaml

@@ -7,6 +7,8 @@ overrides:
       - missing required features
       - \(MDS_CACHE_OVERSIZED\)
       - \(MDS_TRIM\)
+      - \(MDS_CLIENTS_BROKEN_ROOTSQUASH\)
+      - report clients with broken root_squash implementation
 tasks:
   - cephfs_test_runner:
       fail_on_skip: false