[nancy][servers] talc-data is no longer a group storage

data/grid5000/sites/nancy/servers/talc-data.json

 {
   "alias": [
-    "storage3"
+
   ],
   "group_storage": {
     "name": "storage3",

input/grid5000/sites/nancy/servers/physical.yaml

@@ -26,8 +26,7 @@ srv-data2:
 
 talc-data:
   kind: physical
-  alias:
-    - storage3
+  alias: []
   warranty: 2022-11
   serial: 92ZLL82
   network_adapters:
@@ -40,7 +39,6 @@ talc-data:
     size: 180000000000000
     rate: 10000000000
 
-
 talc-data-baie2:
   kind: storage
   alias: []