fix build

package.json

@@ -67,6 +67,7 @@
     "tslint": "^5.20.1",
     "tslint-eslint-rules": "^5.4.0",
     "typescript": "^3.7.3",
+    "uglifyjs-webpack-plugin": "^2.2.0",
     "webpack": "^4.41.3",
     "webpack-cli": "^3.3.10"
   },

yarn.lock

@@ -3458,6 +3458,11 @@ semver@^6.0.0:
   resolved "https://registry.yarnpkg.com/semver/-/semver-6.3.0.tgz#ee0a64c8af5e8ceea67687b133761e1becbd1d3d"
   integrity sha512-b39TBaTSfV6yBrapU89p5fKekE2m/NwnDocOVruQFS1/veMgdzuPcnOM34M6CwxW8jH/lxEa5rBoDeUwu5HHTw==
 
+serialize-javascript@^1.7.0:
+  version "1.9.1"
+  resolved "https://registry.yarnpkg.com/serialize-javascript/-/serialize-javascript-1.9.1.tgz#cfc200aef77b600c47da9bb8149c943e798c2fdb"
+  integrity sha512-0Vb/54WJ6k5v8sSWN09S0ora+Hnr+cX40r9F170nT+mSkaxltoE/7R3OrIdBSUv1OoiobH1QoWQbCnAO+e8J1A==
+
 serialize-javascript@^2.1.2:
   version "2.1.2"
   resolved "https://registry.yarnpkg.com/serialize-javascript/-/serialize-javascript-2.1.2.tgz#ecec53b0e0317bdc95ef76ab7074b7384785fa61"
@@ -3999,14 +4004,29 @@ [email protected]:
     commander "~2.16.0"
     source-map "~0.6.1"
 
-uglify-js@^3.1.4:
+uglify-js@^3.1.4, uglify-js@^3.6.0:
   version "3.7.2"
   resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-3.7.2.tgz#cb1a601e67536e9ed094a92dd1e333459643d3f9"
   integrity sha512-uhRwZcANNWVLrxLfNFEdltoPNhECUR3lc+UdJoG9CBpMcSnKyWA94tc3eAujB1GcMY5Uwq8ZMp4qWpxWYDQmaA==
   dependencies:
     commander "~2.20.3"
     source-map "~0.6.1"
 
+uglifyjs-webpack-plugin@^2.2.0:
+  version "2.2.0"
+  resolved "https://registry.yarnpkg.com/uglifyjs-webpack-plugin/-/uglifyjs-webpack-plugin-2.2.0.tgz#e75bc80e7f1937f725954c9b4c5a1e967ea9d0d7"
+  integrity sha512-mHSkufBmBuJ+KHQhv5H0MXijtsoA1lynJt1lXOaotja8/I0pR4L9oGaPIZw+bQBOFittXZg9OC1sXSGO9D9ZYg==
+  dependencies:
+    cacache "^12.0.2"
+    find-cache-dir "^2.1.0"
+    is-wsl "^1.1.0"
+    schema-utils "^1.0.0"
+    serialize-javascript "^1.7.0"
+    source-map "^0.6.1"
+    uglify-js "^3.6.0"
+    webpack-sources "^1.4.0"
+    worker-farm "^1.7.0"
+
 union-value@^1.0.0:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/union-value/-/union-value-1.0.1.tgz#0b6fe7b835aecda61c6ea4d4f02c14221e109847"