PicarroProvider. Sort by datetime.

src/dataprovider/picarroprovider.py

@@ -39,5 +39,7 @@ class PicarroProvider:
             picarro_df = picarro_df.drop(columns=["DATE", "TIME"])
             picarro_df = picarro_df[(picarro_df["datetime"] >= first_datetime) & (picarro_df["datetime"] <= last_datetime)]
 
+            picarro_df = picarro_df.sort_values(by=['datetime'])
+
             return picarro_df