[ImgBot] Optimize images (#1974)

*Total -- 2,762.12kb -> 2,382.30kb (13.75%)

/static/web_interface_screenshot_start.png -- 106.23kb -> 59.10kb (44.37%)
/docs/source/maigret_screenshot.png -- 375.21kb -> 233.98kb (37.64%)
/static/web_interface_screenshot.png -- 615.65kb -> 424.23kb (31.09%)
/static/recursive_search.svg -- 1,665.02kb -> 1,664.99kb (0%)

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

Author: imgbot[bot]