[ImgBot] Optimize images

*Total -- 46.28kb -> 11.27kb (75.64%)

/assets/icons/pwa/512x512.png -- 16.89kb -> 2.70kb (84.01%)
/assets/icons/pwa/384x384.png -- 11.01kb -> 2.25kb (79.52%)
/assets/icons/pwa/192x192.png -- 4.64kb -> 1.28kb (72.47%)
/assets/icons/pwa/152x152.png -- 3.39kb -> 1.07kb (68.36%)
/assets/icons/pwa/144x144.png -- 3.22kb -> 1.03kb (68.15%)
/assets/icons/pwa/128x128.png -- 2.84kb -> 0.96kb (66.35%)
/assets/icons/pwa/96x96.png -- 2.15kb -> 0.83kb (61.33%)
/assets/icons/pwa/72x72.png -- 1.66kb -> 0.71kb (57.26%)
/assets/images/logo/athendat.png -- 0.47kb -> 0.44kb (6.39%)

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