Bump webpack-merge from 4.1.5 to 4.2.1

Bumps [webpack-merge](https://github.com/survivejs/webpack-merge) from 4.1.5 to 4.2.1.
- [Release notes](https://github.com/survivejs/webpack-merge/releases)
- [Changelog](https://github.com/survivejs/webpack-merge/blob/master/CHANGELOG.md)
- [Commits](https://github.com/survivejs/webpack-merge/compare/v4.1.5...v4.2.1)

Signed-off-by: dependabot[bot] <support@dependabot.com>

package-lock.json

@@ -1030,7 +1030,7 @@
     },
     "Select2": {
       "version": "git+https://github.com/select2/select2.git#b5f3b2839c48c53f9641d6bb1bccafc5260c7620",
-      "from": "git+https://github.com/select2/select2.git#3.4.8"
+      "from": "git+https://github.com/select2/select2.git#b5f3b2839c48c53f9641d6bb1bccafc5260c7620"
     },
     "acorn": {
       "version": "5.7.3",
@@ -2623,7 +2623,8 @@
         "ansi-regex": {
           "version": "2.1.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "aproba": {
           "version": "1.2.0",
@@ -3038,7 +3039,8 @@
         "safe-buffer": {
           "version": "5.1.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "safer-buffer": {
           "version": "2.1.2",
@@ -3094,6 +3096,7 @@
           "version": "3.0.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "ansi-regex": "^2.0.0"
           }
@@ -3137,12 +3140,14 @@
         "wrappy": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "yallist": {
           "version": "3.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         }
       }
     },
@@ -5719,9 +5724,9 @@
       }
     },
     "webpack-merge": {
-      "version": "4.1.5",
-      "resolved": "https://registry.npmjs.org/webpack-merge/-/webpack-merge-4.1.5.tgz",
-      "integrity": "sha512-sVcM+MMJv6DO0C0GLLltx8mUlGMKXE0zBsuMqZ9jz2X9gsekALw6Rs0cAfTWc97VuWS6NpVUa78959zANnMMLQ==",
+      "version": "4.2.1",
+      "resolved": "https://registry.npmjs.org/webpack-merge/-/webpack-merge-4.2.1.tgz",
+      "integrity": "sha512-4p8WQyS98bUJcCvFMbdGZyZmsKuWjWVnVHnAS3FFg0HDaRVrPbkivx2RYCre8UiemD67RsiFFLfn4JhLAin8Vw==",
       "dev": true,
       "requires": {
         "lodash": "^4.17.5"

package.json

@@ -56,6 +56,6 @@
     "url-loader": "^1.1.2",
     "webpack": "^4.28.4",
     "webpack-cli": "^3.1.2",
-    "webpack-merge": "^4.1.5"
+    "webpack-merge": "^4.2.1"
   }
 }