[ImgBot] Optimize images (GoogleCloudPlatform#379)

*Total -- 9,700.78kb -> 7,363.19kb (24.1%)

/docs/img/online-boutique-frontend-1.png -- 5,226.25kb -> 3,464.34kb (33.71%)
/docs/img/online-boutique-frontend-2.png -- 845.23kb -> 570.46kb (32.51%)
/docs/img/architecture-diagram.png -- 70.77kb -> 52.80kb (25.39%)
/src/frontend/static/images/HeroBannerImage.png -- 820.54kb -> 653.61kb (20.34%)
/src/frontend/static/icons/Hipster_DownArrow.svg -- 0.27kb -> 0.22kb (17.86%)
/src/frontend/static/icons/Hipster_HelpIcon.svg -- 0.45kb -> 0.39kb (13.64%)
/src/frontend/static/icons/Hipster_SearchIcon.svg -- 0.36kb -> 0.31kb (13.44%)
/src/frontend/static/images/VRHeadsets.png -- 408.29kb -> 356.61kb (12.66%)
/src/frontend/static/icons/Hipster_ProfileIcon.svg -- 0.51kb -> 0.44kb (12.16%)
/src/frontend/static/icons/Hipster_CheckOutIcon.svg -- 0.51kb -> 0.45kb (12%)
/src/frontend/static/icons/Hipster_PinterestIcon.svg -- 0.59kb -> 0.53kb (10.47%)
/src/frontend/static/icons/Hipster_GooglePlayIcon.svg -- 6.05kb -> 5.42kb (10.42%)
/src/frontend/static/icons/Hipster_TwitterIcon.svg -- 0.51kb -> 0.46kb (9.63%)
/src/frontend/static/icons/Hipster_CartIcon.svg -- 0.67kb -> 0.60kb (9.24%)
/src/frontend/static/icons/Hipster_CurrencyIcon.svg -- 0.68kb -> 0.62kb (9.09%)
/src/frontend/static/img/products/film-camera.jpg -- 145.81kb -> 133.48kb (8.46%)
/src/frontend/static/icons/Hipster_NavLogo.svg -- 2.66kb -> 2.46kb (7.77%)
/src/frontend/static/icons/Hipster_FacebookIcon.svg -- 0.79kb -> 0.73kb (7.75%)
/src/frontend/static/icons/Hipster_YoutubeIcon.svg -- 0.88kb -> 0.82kb (7.51%)
/src/frontend/static/icons/Hipster_InstagramIcon.svg -- 1.06kb -> 0.99kb (6.26%)
/src/frontend/static/img/products/terrarium.jpg -- 55.75kb -> 52.27kb (6.24%)
/src/frontend/static/img/products/air-plant.jpg -- 94.18kb -> 88.69kb (5.83%)
/src/frontend/static/img/products/camera-lens.jpg -- 155.02kb -> 147.69kb (4.73%)
/src/frontend/static/img/products/city-bike.jpg -- 145.42kb -> 140.56kb (3.34%)
/src/frontend/static/images/AdvertBannerImage.png -- 526.28kb -> 510.26kb (3.04%)
/src/frontend/static/img/products/record-player.jpg -- 137.53kb -> 133.64kb (2.83%)
/src/frontend/static/icons/Hipster_HeroLogo.svg -- 15.91kb -> 15.53kb (2.39%)
/src/frontend/static/icons/Hipster_HeroLogoCyan.svg -- 15.92kb -> 15.54kb (2.39%)
/src/frontend/static/img/products/barista-kit.jpg -- 211.11kb -> 206.06kb (2.39%)
/src/frontend/static/img/products/typewriter.jpg -- 82.90kb -> 81.11kb (2.16%)
/src/frontend/static/icons/Hipster_HotProducts.svg -- 8.79kb -> 8.60kb (2.07%)
/src/frontend/static/icons/Hipster_KitchenwareOffer.svg -- 20.21kb -> 19.97kb (1.22%)
/src/frontend/static/icons/Hipster_Advert2.svg -- 19.24kb -> 19.02kb (1.12%)
/src/frontend/static/icons/Hipster_OtherProducts.svg -- 25.76kb -> 25.50kb (1.02%)
/src/frontend/static/images/Advert2BannerImage.png -- 653.90kb -> 653.01kb (0.14%)

Signed-off-by: ImgBotApp <[email protected]>

Co-authored-by: ImgBotApp <[email protected]>

Author: TPS