Odd readings with H3LIS331

Re this thread:
https://forums.adafruit.com/viewtopic.php?f=60&t=176800

Recreated using Pi Zero W:
```python
pi@raspberrypi:~ $ python3
Python 3.7.3 (default, Jul 25 2020, 13:03:44)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import board
>>> import adafruit_lis331
>>> lis = adafruit_lis331.H3LIS331(board.I2C())
>>> lis.acceleration
(-19.15361328125, -47.884033203125, 3.83072265625)
>>> lis.acceleration
(-28.730419921874997, -11.49216796875, 34.47650390625)
>>> lis.acceleration
(-32.561142578125, -7.6614453125, 26.81505859375)
>>> lis.acceleration
(-24.899697265625, -26.81505859375, 30.64578125)
>>>
```

Start by reviewing the linked Adafruit forum thread and reproducing the readings on a Pi Zero W with the shown Python imports and H3LIS331 setup. Compare repeated acceleration values against the sensor's expected stationary behavior; done means the cause is identified and the reported readings are corrected or the expected behavior is documented.

Written by the indexing model from the issue text.