Suppress FutureWarning

```
PriceGenerator.py:487: FutureWarning: Support for nested sequences for 'parse_dates' in pd.read_csv is deprecated. Combine the desired columns with pd.to_datetime after parsing instead.
  self.prices = pd.read_csv(fileName, names=self.csvHeaders, engine="python", sep=self.sep, parse_dates={"datetime": ["date", "time"]})
```