fixup! Don't update the repo unless we need to

update.py

@@ -468,7 +468,7 @@ def main(
             if version is None:
                 version = find_latest_version()
 
-            if version != existing_version and skip_existing:
+            if version != existing_version or not skip_existing:
                 download_locations = download_tzdb_tarballs(version)
             else:
                 download_locations = None