[ImgBot] Optimize images

*Total -- 464.00kb -> 359.80kb (22.46%)

/screenshot.png -- 337.32kb -> 238.12kb (29.41%)
/_icons/30pxwhite.svg -- 4.05kb -> 3.86kb (4.56%)
/_icons/60pxwhite.svg -- 4.15kb -> 3.96kb (4.52%)
/_icons/30pxblue.svg -- 4.05kb -> 3.87kb (4.49%)
/_icons/90pxwhite.svg -- 4.19kb -> 4.00kb (4.46%)
/_icons/60pxblue.svg -- 4.15kb -> 3.96kb (4.45%)
/_icons/30pxblack.svg -- 3.98kb -> 3.81kb (4.44%)
/_icons/128pxwhite.svg -- 4.23kb -> 4.04kb (4.43%)
/_icons/60pxblack.svg -- 4.08kb -> 3.90kb (4.4%)
/_icons/90pxblue.svg -- 4.19kb -> 4.00kb (4.39%)
/_icons/128pxblue.svg -- 4.23kb -> 4.04kb (4.36%)
/_icons/90pxblack.svg -- 4.12kb -> 3.94kb (4.34%)
/_icons/256pxwhite.svg -- 4.36kb -> 4.18kb (4.32%)
/_icons/128pxblack.svg -- 4.16kb -> 3.99kb (4.27%)
/_icons/256pxblue.svg -- 4.36kb -> 4.18kb (4.25%)
/_icons/256pxblack.svg -- 4.30kb -> 4.12kb (4.2%)
/_icons/512pxwhite.svg -- 4.56kb -> 4.37kb (4.16%)
/_icons/512pxblue.svg -- 4.56kb -> 4.37kb (4.09%)
/_icons/512pxblack.svg -- 4.49kb -> 4.31kb (4.04%)
/_icons/logotype1white.svg -- 8.46kb -> 8.17kb (3.37%)
/_icons/logotype1black.svg -- 8.16kb -> 7.88kb (3.36%)
/_icons/logotype2white.svg -- 8.56kb -> 8.28kb (3.36%)
/_icons/logotype2black.svg -- 8.26kb -> 7.99kb (3.36%)
/_icons/logotype1blue.svg -- 8.46kb -> 8.18kb (3.34%)
/_icons/logotype2blue.svg -- 8.56kb -> 8.28kb (3.33%)

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