config-backend-pull must use the current config

databaseConfigFetch comment says:

srv_cfg pointer to the staging configuration that should hold the config backends list and other partial configuration read from the file in case the method is called upon the server's start up. It is a pointer to the current server configuration if the method is called to fetch configuration updates.

commandConfigBackendPullHandler code was copied from cbFetchUpdates which establishes the periodic update. The problem is that cbFetchUpdates puts the staging config in the closure before the config manager commit when the handler is called after so it should be fixed to use the current config.