Bump chalk from 2.4.2 to 4.0.0

Bumps [chalk](https://github.com/chalk/chalk) from 2.4.2 to 4.0.0.
- [Release notes](https://github.com/chalk/chalk/releases)
- [Commits](https://github.com/chalk/chalk/compare/v2.4.2...v4.0.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -9,7 +9,7 @@
   "devDependencies": {
     "@babel/core": "^7.4.5",
     "@babel/preset-env": "^7.4.5",
-    "chalk": "^2.4.2",
+    "chalk": "^4.0.0",
     "clean-css-cli": "^4.3.0",
     "core-js": "^3.1.4",
     "cross-env": "^6.0.3",