chore(package): update autoprefixer to version 6.4.0
chore(package): update autoprefixer to version 6.4.0

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Svatok/react-todo,zakkriel/love-quest,tgallin/accompagnerlautisme,reactGo/reactGo,SrSandeepKumar/TheWeatherApp,mohammed52/door-quote-automator,davidychow87/etf,denistakeda/LifeBalance,gajananpp/DS,reactGo/reactGo,denistakeda/LifeBalance,agroves333/banno,phoniks/JustUs-1,johnware15/upbeat-crane,choonkending/react-webpack-node,avloss/reactGo,jonatay/linkupAdmin,minicooperj/MegdProject,minicooperj/MegdProject,denistakeda/LifeBalance,agroves333/sf,andrewmoon1/moon-codes