How to convert and optimize an image to webp in one step with default settings? #284
Description
Currently, zimscraperlib makes a distinction between conversion (to another format) and optimization (compression).
This is not really convenient in the case I have at hand (gutenberg scraper) where I have any image I want to convert to WEBP and optimize with default zimscraperlib options/presets. Both in terms of code (two functions to call) and computing efficiency (probably more memory / disk to allocate, and maybe even more CPU power). In could even have adverse effects in terms of final results.