Update configuration.md

configuration.md

@@ -6,7 +6,7 @@ https://github.com/ceph/ceph/tree/master/src/common/options
 ```
 Or querying the daemon
 ```
-ceph daemon	<type.id>	config <diff|get|set|show>
+ceph daemon <type.id> config <diff|get|set|show>
 "config diff": "dump diff of current config and default config"
 "config get": "config get <field>: get the config value"
 "config set": "config set <field> <val> [<val> ...]: set a config variable"