Update dev dependencies (#3401)

- Everything still works as expected.
  - Remove bundlesize
    - It still uses libtorb which is deprecated and broken on Win and
      requires a full suite of build tools on Mac. Keeping it in the
      package makes it difficult for anyone filing issues to run tests.
    - See: #3396
  - Update grunt and it's plugins
  - Update karma to v4...so much faster!
    - Changed the karma config. Better changes: #3394
  - Update Webpack
    - Uses terser over uglify
  - Update eslint
    - Caused an error in util.js from the `global` directive so the
      directive is removed (it was not needed).
  - Update typescript
    - The old version of tsc didn't know about new features in
      @types/node (like `asserts value`).

Co-authored-by: Jay <jasonsaayman@gmail.com>

package.json

@@ -4,7 +4,7 @@
   "description": "Promise based HTTP client for the browser and node.js",
   "main": "index.js",
   "scripts": {
-    "test": "grunt test && bundlesize",
+    "test": "grunt test",
     "start": "node ./sandbox/server.js",
     "build": "NODE_ENV=production grunt build",
     "preversion": "npm test",
@@ -32,41 +32,38 @@
   },
   "homepage": "https://github.com/axios/axios",
   "devDependencies": {
-    "bundlesize": "^0.17.0",
     "coveralls": "^3.0.0",
     "es6-promise": "^4.2.4",
-    "grunt": "^1.0.2",
+    "grunt": "^1.3.0",
     "grunt-banner": "^0.6.0",
     "grunt-cli": "^1.2.0",
     "grunt-contrib-clean": "^1.1.0",
     "grunt-contrib-watch": "^1.0.0",
-    "grunt-eslint": "^20.1.0",
-    "grunt-karma": "^2.0.0",
+    "grunt-eslint": "^23.0.0",
+    "grunt-karma": "^4.0.0",
     "grunt-mocha-test": "^0.13.3",
     "grunt-ts": "^6.0.0-beta.19",
-    "grunt-webpack": "^1.0.18",
+    "grunt-webpack": "^4.0.2",
     "istanbul-instrumenter-loader": "^1.0.0",
     "jasmine-core": "^2.4.1",
-    "karma": "^1.3.0",
-    "karma-chrome-launcher": "^2.2.0",
-    "karma-coverage": "^1.1.1",
-    "karma-firefox-launcher": "^1.1.0",
+    "karma": "^5.2.3",
+    "karma-chrome-launcher": "^3.1.0",
+    "karma-firefox-launcher": "^2.1.0",
     "karma-jasmine": "^1.1.1",
     "karma-jasmine-ajax": "^0.1.13",
-    "karma-opera-launcher": "^1.0.0",
     "karma-safari-launcher": "^1.0.0",
-    "karma-sauce-launcher": "^1.2.0",
     "karma-sinon": "^1.0.5",
-    "karma-sourcemap-loader": "^0.3.7",
-    "karma-webpack": "^1.7.0",
+    "karma-sourcemap-loader": "^0.3.8",
+    "karma-webpack": "^4.0.2",
     "load-grunt-tasks": "^3.5.2",
     "minimist": "^1.2.0",
-    "mocha": "^5.2.0",
+    "mocha": "^8.2.1",
     "sinon": "^4.5.0",
-    "typescript": "^2.8.1",
+    "terser-webpack-plugin": "^4.2.3",
+    "typescript": "^4.0.5",
     "url-search-params": "^0.10.0",
-    "webpack": "^1.13.1",
-    "webpack-dev-server": "^1.14.1"
+    "webpack": "^4.44.2",
+    "webpack-dev-server": "^3.11.0"
   },
   "browser": {
     "./lib/adapters/http.js": "./lib/adapters/xhr.js"