fix(package): update chalk to version 4.0.0

Closes #8

Author: greenkeeper[bot]

package.json

@@ -33,7 +33,7 @@
     "@babel/preset-env": "^7.8.2",
     "basic-auth": "^2.0.0",
     "body-parser": "^1.18.2",
-    "chalk": "^2.4.1",
+    "chalk": "^4.0.0",
     "debug": "^4.1.1",
     "ejs": "^3.0.1",
     "express": "^4.16.2",