Update webpack-merge to version 4.2.1

Author: depfu[bot]

package.json

@@ -45,7 +45,7 @@
     "serve-favicon": "^2.5.0",
     "webpack-dev-middleware": "^3.4.0",
     "webpack-hot-middleware": "^2.24.3",
-    "webpack-merge": "^4.1.4",
+    "webpack-merge": "^4.2.1",
     "webpack-node-externals": "^1.7.2",
     "webpackbar": "^2.6.3"
   },

yarn.lock

@@ -8201,13 +8201,20 @@ webpack-log@^2.0.0:
     ansi-colors "^3.0.0"
     uuid "^3.3.2"
 
-webpack-merge@^4.1.2, webpack-merge@^4.1.4:
+webpack-merge@^4.1.2:
   version "4.1.5"
   resolved "https://registry.yarnpkg.com/webpack-merge/-/webpack-merge-4.1.5.tgz#2be31e846c20767d1bef56bdca64c328a681190a"
   integrity sha512-sVcM+MMJv6DO0C0GLLltx8mUlGMKXE0zBsuMqZ9jz2X9gsekALw6Rs0cAfTWc97VuWS6NpVUa78959zANnMMLQ==
   dependencies:
     lodash "^4.17.5"
 
+webpack-merge@^4.2.1:
+  version "4.2.1"
+  resolved "https://registry.yarnpkg.com/webpack-merge/-/webpack-merge-4.2.1.tgz#5e923cf802ea2ace4fd5af1d3247368a633489b4"
+  integrity sha512-4p8WQyS98bUJcCvFMbdGZyZmsKuWjWVnVHnAS3FFg0HDaRVrPbkivx2RYCre8UiemD67RsiFFLfn4JhLAin8Vw==
+  dependencies:
+    lodash "^4.17.5"
+
 webpack-node-externals@^1.7.2:
   version "1.7.2"
   resolved "https://registry.yarnpkg.com/webpack-node-externals/-/webpack-node-externals-1.7.2.tgz#6e1ee79ac67c070402ba700ef033a9b8d52ac4e3"