Change autoprefix browser specific key

Author: windyakin

build/postcss.config.js

@@ -13,7 +13,7 @@ module.exports = () => {
       autoprefixer: {
         cascade: false,
         // https://github.com/twbs/bootstrap/blob/v4.0.0/package.json#L136-L147
-        browsers: [
+        overrideBrowserslist: [
           'last 1 major version',
           '>= 1%',
           'Chrome >= 45',