Build: Fix Travis build on Node.js 15 with npm 7

The `grunt-karma` version we used required Karma 3.x and it's now enforced
in npm 7. Update a few Karma & Grunt-related packages to resolve the issue.

Closes gh-4810

package.json

@@ -23,14 +23,13 @@
     "url": "https://github.com/jquery/jquery/issues"
   },
   "license": "MIT",
-  "dependencies": {},
   "devDependencies": {
     "@babel/core": "7.3.3",
     "@babel/plugin-transform-for-of": "7.2.0",
     "commitplease": "3.2.0",
     "core-js": "2.6.5",
     "eslint-config-jquery": "3.0.0",
-    "grunt": "1.0.3",
+    "grunt": "1.3.0",
     "grunt-babel": "8.0.0",
     "grunt-cli": "1.3.2",
     "grunt-compare-size": "0.4.2",
@@ -39,21 +38,21 @@
     "grunt-eslint": "22.0.0",
     "grunt-git-authors": "3.2.0",
     "grunt-jsonlint": "1.1.0",
-    "grunt-karma": "3.0.1",
+    "grunt-karma": "4.0.0",
     "grunt-newer": "1.3.0",
-    "grunt-npmcopy": "0.1.0",
+    "grunt-npmcopy": "0.2.0",
     "gzip-js": "0.3.2",
     "husky": "1.3.1",
     "insight": "0.10.1",
     "jsdom": "13.2.0",
-    "karma": "4.0.1",
+    "karma": "5.2.3",
     "karma-browserstack-launcher": "1.4.0",
     "karma-chrome-launcher": "2.2.0",
     "karma-firefox-launcher": "1.1.0",
     "karma-ie-launcher": "1.0.0",
-    "karma-jsdom-launcher": "7.1.0",
+    "karma-jsdom-launcher": "8.0.2",
     "karma-qunit": "3.0.0",
-    "load-grunt-tasks": "4.0.0",
+    "load-grunt-tasks": "5.1.0",
     "native-promise-only": "0.8.1",
     "promises-aplus-tests": "2.1.2",
     "q": "1.5.1",
@@ -63,7 +62,7 @@
     "sinon": "2.3.7",
     "sizzle": "2.3.5",
     "strip-json-comments": "2.0.1",
-    "testswarm": "1.1.0",
+    "testswarm": "1.1.2",
     "uglify-js": "3.4.7"
   },
   "scripts": {