qa/tasks: Initialize 'monitoring_profiles' spec to an empty dict

Initialize 'monitoring_profiles' to an empty python dictionary instead of
'None' to prevent the cbt task from failing due to the TypeError exception
when attempting to iterate a 'NoneType'.

The bug was introduced as part of ceph#51438
and commit e174c6e.

Signed-off-by: Sridhar Seshasayee <[email protected]>
Fixes: https://tracker.ceph.com/issues/66799

Author: sseshasa

qa/tasks/cbt.py

@@ -64,7 +64,7 @@ def generate_cbt_config(self):
                    (remote.ssh.get_transport().getpeername() for (remote, role_list) in remotes_and_roles)]
             benchmark_config['cosbench']['auth'] = "username=cosbench:operator;password=intel2012;url=http://%s:80/auth/v1.0;retry=9" %(ips[0])
         client_endpoints_config = self.config.get('client_endpoints', None)
-        monitoring_profiles = self.config.get('monitoring_profiles', None)
+        monitoring_profiles = self.config.get('monitoring_profiles', {})
 
         return dict(
             cluster=cluster_config,