fix tablereport error in histogram when data range is very narrow

[jeromedockes]

we can get an error in matplotlib / numpy histogram if the column is not constant but the data range does not contain enough representable floating numbers for the default number of bins

for example it would fail on a column like this

    low = np.float32(10.0)
    high = np.nextafter(low, 11.0)
    data = pd.Series([low, high])