fix(package): update chalk to version 4.0.0

Closes #12

Author: greenkeeper[bot]

package.json

@@ -65,7 +65,7 @@
     "@oclif/command": "^1",
     "@oclif/config": "^1.12.12",
     "@oclif/plugin-help": "^2.1.6",
-    "chalk": "^2.4.2",
+    "chalk": "^4.0.0",
     "cli-ux": "^5.2.1",
     "emojic": "^1.1.15",
     "enquirer": "^2.3.0",