eslint: Remove unused dependency on 'debug' (#1097)

It stopped being used as of #852.

Closes #1096.

Author: edmorley

packages/eslint/package.json

@@ -24,7 +24,6 @@
   },
   "dependencies": {
     "babel-eslint": "^9.0.0",
-    "debug": "^3.1.0",
     "deepmerge": "^1.5.2",
     "eslint-loader": "^2.1.0",
     "eslint-plugin-babel": "^5.1.0",