fix(package): update debug to version 4.0.0

Author: greenkeeper[bot]

Diff for: package.json

@@ -18,7 +18,7 @@
   "dependencies": {
     "@semantic-release/error": "^2.1.0",
     "aggregate-error": "^1.0.0",
-    "debug": "^3.1.0",
+    "debug": "^4.0.0",
     "dir-glob": "^2.0.0",
     "execa": "^1.0.0",
     "fs-extra": "^7.0.0",