Update dependency webpack to v4.39.2

package.json

@@ -75,7 +75,7 @@
     "redux-thunk": "2.3.0",
     "taskcluster-client-web": "8.1.1",
     "taskcluster-lib-scopes": "10.0.2",
-    "webpack": "4.39.1",
+    "webpack": "4.39.2",
     "webpack-cli": "3.3.6"
   },
   "devDependencies": {

yarn.lock

@@ -9537,10 +9537,10 @@ webpack-sources@^1.1.0, webpack-sources@^1.4.0, webpack-sources@^1.4.1:
     source-list-map "^2.0.0"
     source-map "~0.6.1"
 
-webpack@4.39.1:
-  version "4.39.1"
-  resolved "https://registry.yarnpkg.com/webpack/-/webpack-4.39.1.tgz#60ed9fb2b72cd60f26ea526c404d2a4cc97a1bd8"
-  integrity sha512-/LAb2TJ2z+eVwisldp3dqTEoNhzp/TLCZlmZm3GGGAlnfIWDgOEE758j/9atklNLfRyhKbZTCOIoPqLJXeBLbQ==
+webpack@4.39.2:
+  version "4.39.2"
+  resolved "https://registry.yarnpkg.com/webpack/-/webpack-4.39.2.tgz#c9aa5c1776d7c309d1b3911764f0288c8c2816aa"
+  integrity sha512-AKgTfz3xPSsEibH00JfZ9sHXGUwIQ6eZ9tLN8+VLzachk1Cw2LVmy+4R7ZiwTa9cZZ15tzySjeMui/UnSCAZhA==
   dependencies:
     "@webassemblyjs/ast" "1.8.5"
     "@webassemblyjs/helper-module-context" "1.8.5"