Has SPI mode been tested?

Re this thread:
https://forums.adafruit.com/viewtopic.php?p=946036#p946036

The guide currently does not cover SPI usage.
https://learn.adafruit.com/adafruit-9-dof-orientation-imu-fusion-breakout-bno085/python-circuitpython

The library example has some code that looks copy-pasta'd (D9 ref'd twice, reset pin set as input) and the instantiation does not match the actual [ctor](https://github.com/adafruit/Adafruit_CircuitPython_BNO08x/blob/c8c7cf01199c658db83e00266f84bb13eb3bab99/adafruit_bno08x/i2c.py#L24):
https://github.com/adafruit/Adafruit_CircuitPython_BNO08x/blob/c8c7cf01199c658db83e00266f84bb13eb3bab99/examples/bno08x_simpletest_spi.py#L19-L25

Additionally, there does not appear to be any code in place to perform the required PS0/Wake pin assertion needed for SPI transactions:

Start with examples/bno08x_simpletest_spi.py and compare its constructor usage with adafruit_bno08x/i2c.py. Review the linked forum thread and SPI pin requirements, then check the Python/CircuitPython guide. Done means the SPI example and required PS0/Wake handling are validated and the guide accurately covers SPI usage.

Written by the indexing model from the issue text.