[ImgBot] Optimize images

*Total -- 306.57kb -> 263.80kb (13.95%)

/assets/star.png -- 1.58kb -> 0.75kb (52.14%)
/assets/console_table.png -- 19.36kb -> 10.19kb (47.37%)
/assets/rendering-process.png -- 16.89kb -> 12.70kb (24.83%)
/assets/console.log.png -- 16.42kb -> 12.76kb (22.29%)
/assets/console.error.png -- 19.35kb -> 15.55kb (19.67%)
/assets/console_dir.png -- 25.24kb -> 20.33kb (19.49%)
/assets/console.warn.png -- 20.93kb -> 16.89kb (19.31%)
/assets/console_log.png -- 44.11kb -> 35.74kb (18.97%)
/assets/html-dom-tree.png -- 44.24kb -> 40.89kb (7.57%)
/assets/deepcopy.png -- 61.01kb -> 60.66kb (0.57%)
/assets/rendering.png -- 37.45kb -> 37.35kb (0.25%)

Signed-off-by: ImgBotApp <ImgBotHelp@gmail.com>

Author: ImgBotApp