fix(typescript): use @types/webpack-env instead of @types/node

fixes #2531

Author: haoqunjiang

packages/@vue/cli-plugin-typescript/generator/template/tsconfig.json

@@ -14,7 +14,7 @@
     "sourceMap": true,
     "baseUrl": ".",
     "types": [
-      "node"<% if (hasMocha || hasJest) { %>,<% } %>
+      "webpack-env"<% if (hasMocha || hasJest) { %>,<% } %>
       <%_ if (hasMocha) { _%>
       "mocha",
       "chai"

packages/@vue/cli-plugin-typescript/package.json

@@ -22,7 +22,7 @@
     "access": "public"
   },
   "dependencies": {
-    "@types/node": "^10.5.2",
+    "@types/webpack-env": "^1.13.6",
     "@vue/cli-shared-utils": "^3.0.2",
     "fork-ts-checker-webpack-plugin": "^0.4.4",
     "globby": "^8.0.1",