fix(deps): update dependency dotenv to v7 (#109)

Author: renovate[bot]

package.json

@@ -54,7 +54,7 @@
   "dependencies": {
     "chalk": "^2.0.0",
     "commander": "^2.9.0",
-    "dotenv": "^6.0.0",
+    "dotenv": "^7.0.0",
     "glob": "^7.1.1",
     "lintspaces": "0.6.3",
     "minimatch": "^3.0.3",