* Update image_processing.py
Adds save timestamp file and adds last_detection attribute
* Update test_image_processing.py
Adds test
* Adds assert pil_img.save.call_args
* Test timestamp filename
* Add test bad data
* Update test_image_processing.py
* Fix bad image data test
* Update homeassistant/components/sighthound/image_processing.py
Co-Authored-By: Martin Hjelmare <marhje52@gmail.com>
Co-authored-by: Martin Hjelmare <marhje52@gmail.com>