fix: Expand access list owner, items, clients and proxy hosts

Author: Sander0542

backend/schema/paths/nginx/access-lists/listID/get.json

@@ -22,6 +22,20 @@
             },
             "required": true,
             "example": 1
+        },
+        {
+            "in": "query",
+            "name": "expand",
+            "description": "Expansions",
+            "schema": {
+                "type": "string",
+                "enum": [
+                    "owner",
+                    "items",
+                    "clients",
+                    "proxy_hosts"
+                ]
+            }
         }
     ],
     "responses": {