[DATALAD RUNCMD] Update folder mapping for src/unfccc_ghg_data/unfccc_reader

=== Do not change lines below ===
{
 "chain": [],
 "cmd": "python3 src/unfccc_ghg_data/helper/folder_mapping.py --folder=src/unfccc_ghg_data/unfccc_reader",
 "dsid": "4d062170-604c-4efd-afbf-5ce7f97e0e63",
 "exit": 0,
 "extra_inputs": [],
 "inputs": [],
 "outputs": [
  "src/unfccc_ghg_data/unfccc_reader/folder_mapping.json"
 ],
 "pwd": "."
}
^^^ Do not change lines above ^^^

src/unfccc_ghg_data/unfccc_reader/folder_mapping.json

@@ -23,5 +23,6 @@
     "PER": "Peru",
     "SGP": "Singapore",
     "THA": "Thailand",
-    "TWN": "Taiwan"
+    "TWN": "Taiwan",
+    "USA": "United_States_of_America"
 }