[ImgBot] Optimize images

*Total -- 1,413.12kb -> 1,215.63kb (13.98%)

/images/sponsors/bronze/aops.png -- 33.20kb -> 12.67kb (61.84%)
/images/sponsors/bronze/certopus.png -- 25.55kb -> 11.33kb (55.67%)
/images/sponsors/gold/ivyinstitute.png -- 102.49kb -> 78.81kb (23.11%)
/images/sponsors/gold/cw-e.png -- 320.34kb -> 254.58kb (20.53%)
/android-chrome-192x192.png -- 49.12kb -> 41.37kb (15.77%)
/apple-touch-icon.png -- 43.99kb -> 37.19kb (15.45%)
/android-chrome-512x512.png -- 278.22kb -> 245.73kb (11.68%)
/images/sponsors/bronze/Defang Software Labs Logo.png -- 60.31kb -> 54.40kb (9.81%)
/assets/bg3.svg -- 0.66kb -> 0.62kb (5.89%)
/assets/bg4.svg -- 0.66kb -> 0.62kb (5.88%)
/images/sponsors/bronze/codecrafters.png -- 450.33kb -> 431.27kb (4.23%)
/images/sponsors/bronze/ACS.png -- 27.37kb -> 26.34kb (3.79%)
/favicon-32x32.png -- 2.09kb -> 2.03kb (2.53%)
/assets/bg.svg -- 18.79kb -> 18.67kb (0.61%)

Signed-off-by: ImgBotApp <ImgBotHelp@gmail.com>

Author: ImgBotApp