[ImgBot] Optimize images

*Total -- 3,113.10kb -> 2,704.20kb (13.14%)

/resource/ss4.png -- 159.43kb -> 119.53kb (25.02%)
/resource/git4.png -- 2,278.22kb -> 1,989.29kb (12.68%)
/resource/apg2.png -- 285.37kb -> 249.71kb (12.5%)
/resource/apg4.png -- 390.09kb -> 345.67kb (11.39%)

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

Author: ImgBotApp