[ImgBot] Optimize images

*Total -- 1,310.35kb -> 897.85kb (31.48%)

/extra_tests/snippets/imghdrdata/python.gif -- 0.60kb -> 0.40kb (33.61%)
/wasm/notebook/screenshot.png -- 1,291.41kb -> 880.62kb (31.81%)
/logo.png -- 18.34kb -> 16.83kb (8.22%)

Signed-off-by: ImgBotApp <[email protected]>

Author: ImgBotApp