Add missing underscore

Author: znichollscr

python-packages/input4MIPs-CVs/src/input4MIPs_CVs/cli/update-esgf-scrape.py

@@ -161,7 +161,7 @@ def fix_timestamp(v: str | list | None) -> str | None:
                 msg = f"Unexpected value for {source_id=} for {source_id['_timestamp']}"
                 raise AssertionError(msg)
 
-            res[k]["timestamp"] = res[k]["timestamp"][0]
+            res[k]["_timestamp"] = res[k]["_timestamp"][0]
 
     return res