deps: upgrade `chalk` to v4

package.json

@@ -63,7 +63,7 @@
     "browser-sync": "2.26.7",
     "browserify": "16.5.2",
     "chai": "4.2.0",
-    "chalk": "2.4.2",
+    "chalk": "^4.1.1",
     "cheerio-select-tmp": "^0.1.1",
     "concat-stream": "^2.0.0",
     "cssnano": "4.1.10",