chore(deps): update dependency uglifyjs-webpack-plugin to v2

Author: renovate-bot

package.json

@@ -99,7 +99,7 @@
     "tslint": "^5.11.0",
     "tslint-language-service": "^0.9.6",
     "typescript": "^3.0.1",
-    "uglifyjs-webpack-plugin": "^1.3.0",
+    "uglifyjs-webpack-plugin": "^2.0.0",
     "web-ext": "^2.5.0",
     "webpack": "^4.6.0",
     "worker-loader": "^2.0.0"

yarn.lock

@@ -15221,7 +15221,7 @@ uglify-es@^3.3.4:
     commander "~2.13.0"
     source-map "~0.6.1"
 
-uglify-js@^3.1.4:
+uglify-js@^3.0.0, uglify-js@^3.1.4:
   version "3.4.9"
   resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-3.4.9.tgz#af02f180c1207d76432e473ed24a28f4a782bae3"
   integrity sha512-8CJsbKOtEbnJsTyv6LE6m6ZKniqMiFWmm9sRbopbkGs3gMPPfd3Fh8iIA4Ykv5MgaTbqHr4BaoGLJLZNhsrW1Q==
@@ -15243,17 +15243,17 @@ uglifyjs-webpack-plugin@^1.2.4:
     webpack-sources "^1.1.0"
     worker-farm "^1.5.2"
 
-uglifyjs-webpack-plugin@^1.3.0:
-  version "1.3.0"
-  resolved "https://registry.yarnpkg.com/uglifyjs-webpack-plugin/-/uglifyjs-webpack-plugin-1.3.0.tgz#75f548160858163a08643e086d5fefe18a5d67de"
-  integrity sha512-ovHIch0AMlxjD/97j9AYovZxG5wnHOPkL7T1GKochBADp/Zwc44pEWNqpKl1Loupp1WhFg7SlYmHZRUfdAacgw==
+uglifyjs-webpack-plugin@^2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/uglifyjs-webpack-plugin/-/uglifyjs-webpack-plugin-2.0.1.tgz#f346af53ed496ce72fef462517d417f62bec3010"
+  integrity sha512-1HhCHkOB6wRCcv7htcz1QRPVbWPEY074RP9vzt/X0LF4xXm9l4YGd0qja7z88abDixQlnVwBjXsTBs+Xsn/eeQ==
   dependencies:
-    cacache "^10.0.4"
-    find-cache-dir "^1.0.0"
-    schema-utils "^0.4.5"
+    cacache "^11.2.0"
+    find-cache-dir "^2.0.0"
+    schema-utils "^1.0.0"
     serialize-javascript "^1.4.0"
     source-map "^0.6.1"
-    uglify-es "^3.3.4"
+    uglify-js "^3.0.0"
     webpack-sources "^1.1.0"
     worker-farm "^1.5.2"