fix(webpack.config.*.js): fix tests after autoprefixer upgrade

Author: jlengrand

config/webpack.config.dev.js

@@ -210,13 +210,14 @@ module.exports = {
             options: {
               // Necessary for external CSS imports to work
               // https://github.com/facebook/create-react-app/issues/2677
-              ident: 'postcss',
-              plugins: () => [
-                require('postcss-flexbugs-fixes'),
-                autoprefixer({
-                  flexbox: 'no-2009',
-                }),
-              ],
+              postcssOptions: {
+                plugins: () => [
+                  require('postcss-flexbugs-fixes'),
+                  autoprefixer({
+                    flexbox: 'no-2009',
+                  }),
+                ],
+              },
             },
           },
         ],

config/webpack.config.prod.js

@@ -261,13 +261,14 @@ module.exports = {
             options: {
               // Necessary for external CSS imports to work
               // https://github.com/facebook/create-react-app/issues/2677
-              ident: 'postcss',
-              plugins: () => [
-                require('postcss-flexbugs-fixes'),
-                autoprefixer({
-                  flexbox: 'no-2009',
-                }),
-              ],
+              postcssOptions: {
+                plugins: () => [
+                  require('postcss-flexbugs-fixes'),
+                  autoprefixer({
+                    flexbox: 'no-2009',
+                  }),
+                ],
+              },
             },
           },
         ],

package.json

@@ -49,7 +49,7 @@
     "object-assign": "4.1.1",
     "optimize-css-assets-webpack-plugin": "5.0.3",
     "postcss-flexbugs-fixes": "4.2.1",
-    "postcss-loader": "3.0.0",
+    "postcss-loader": "4.0.3",
     "postcss-safe-parser": "4.0.2",
     "promise": "8.1.0",
     "prompt": "1.0.0",
@@ -141,4 +141,3 @@
     }
   }
 }
-