!fixup Improve test

Author: StanFromIreland

Lib/test/test_tomllib/data/valid/trailing-comma.json

@@ -1,10 +1,9 @@
-{
-  "arr":
-    {"type":"array","value":
-      [
-        {"type":"integer","value":"1"}
-      ]
-    },
+{"arr":
+  {"type":"array","value":
+    [
+      {"type":"integer","value":"1"}
+    ]
+  },
   "tbl": {"a":{"type":"integer","value":"1"}},
   "tbl2": {"b":{"type":"integer","value":"2"}}
 }