Add pikepdf image extractor

[mara004]

I'd be interested in seeing pikepdf in the image extraction benchmark. It provides some pretty sophisticated code that can, in many cases, extract and save PDF images without needing to decode/re-encode the raw data (i. e. without degrading quality/compression).

https://pikepdf.readthedocs.io/en/latest/topics/images.html
https://github.com/pikepdf/pikepdf/blob/master/src/pikepdf/models/image.py