qa: extend MDS heartbeat grace for valgrind

Valgrind makes the MDS slowwwww. The newish mds_heartbeat_grace config allows
us to keep sending beacons to the mons even if the internal heartbeat is slow.
This avoids the laggy messages which are useful to grep for unrelated messaging
issues.

Fixes: http://tracker.ceph.com/issues/38723
Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>
(cherry picked from commit 7b52075)

qa/suites/fs/verify/validater/valgrind.yaml

@@ -1,21 +1,20 @@
 # see http://tracker.ceph.com/issues/20360 and http://tracker.ceph.com/issues/18126
 os_type: centos
 
-# Valgrind makes everything slow, so ignore slow requests
-overrides:
-  ceph:
-    log-whitelist:
-      - slow requests are blocked
-
 overrides:
   install:
     ceph:
       flavor: notcmalloc
       debuginfo: true
   ceph:
+    # Valgrind makes everything slow, so ignore slow requests and extend heartbeat grace
+    log-whitelist:
+      - slow requests are blocked
     conf:
       global:
         osd heartbeat grace: 40
+      mds:
+        mds heartbeat grace: 60
       mon:
         mon osd crush smoke test: false
     valgrind: