Set the 'resample_rule' to the correct value for all sampling values.

toarstats/interface.py

@@ -105,6 +105,8 @@ def calculate_statistics(
         sampling, statistics, data, metadata, seasons, crops, data_capture,
         datetimes, values, station_lat, station_lon, station_climatic_zone
     )
+    resample_rule = ("seasonal" if input_parameters.sampling == "vegseason"
+                     else input_parameters.sampling)
     reference_data_frame = create_reference_data_frame(
         input_parameters.data.index
     )