[ImgBot] Optimize images

*Total -- 484.02kb -> 404.67kb (16.39%)

/ss2.png -- 264.13kb -> 216.38kb (18.08%)
/ss1.png -- 209.04kb -> 177.62kb (15.03%)
/ios/Runner/Assets.xcassets/AppIcon.appiconset/[email protected] -- 10.85kb -> 10.68kb (1.62%)

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

Author: ImgBotApp