[ImgBot] Optimize images

*Total -- 864.08kb -> 798.27kb (7.62%)

/public/apple-touch-icon.png -- 12.46kb -> 10.19kb (18.21%)
/docs/images/bt/bt-install-5.jpeg -- 73.65kb -> 66.38kb (9.87%)
/docs/images/bt/bt-install-6.jpeg -- 145.73kb -> 133.10kb (8.66%)
/docs/images/bt/bt-install-3.jpeg -- 116.80kb -> 106.81kb (8.55%)
/docs/images/bt/bt-install-4.jpeg -- 159.02kb -> 145.49kb (8.5%)
/docs/images/bt/bt-install-1.jpeg -- 160.86kb -> 150.27kb (6.58%)
/docs/images/bt/bt-install-2.jpeg -- 195.56kb -> 186.02kb (4.88%)

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

Author: ImgBotApp