GFS data retrieval produces warning messages in log

[EHJ-52n]

Executed request:

https://maridata.dev.52north.org/EnvDataAPI/request_env_data?
    date_lo=2023-01-25T03%3A44&date_hi=2023-01-27T09%3A55&
    lat_lo=53.08&lat_hi=55.08&
    lon_lo=1.69&lon_hi=6.1&
    GFS=Temperature_surface&format=csv

2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[2]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[4]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[3]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[1]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[41]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[1]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[1]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[1]" to int. Keeping type as str.
2023-01-31 09:54:15 WARNING [1:MainProcess siphon.ncss_dataset.handle_typed_values():81] Cannot convert "[3]" to int. Keeping type as str.