[ImgBot] Optimize images

*Total -- 301.90kb -> 261.30kb (13.45%)

/readme assets/Screenshot (264).png -- 54.10kb -> 42.92kb (20.66%)
/readme assets/Screenshot (257).png -- 41.27kb -> 33.76kb (18.19%)
/readme assets/Screenshot (258).png -- 18.03kb -> 15.63kb (13.34%)
/readme assets/Screenshot (259).png -- 60.61kb -> 52.61kb (13.2%)
/readme assets/Screenshot (262).png -- 23.58kb -> 20.91kb (11.33%)
/readme assets/Screenshot (265).png -- 22.11kb -> 19.83kb (10.29%)
/readme assets/Screenshot (263).png -- 55.76kb -> 50.69kb (9.09%)
/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png -- 10.40kb -> 9.54kb (8.33%)
/app/src/main/res/mipmap-xxhdpi/ic_launcher.png -- 7.72kb -> 7.27kb (5.88%)
/app/src/main/res/mipmap-hdpi/ic_launcher.png -- 3.51kb -> 3.43kb (2.14%)
/app/src/main/res/mipmap-xhdpi/ic_launcher.png -- 4.81kb -> 4.71kb (2.07%)

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