chore(deps): update dependency mock-fs to v4.12.0

Author: renovate-bot

package-lock.json

@@ -45,7 +45,7 @@
     "@types/js-yaml": "3.12.1",
     "@types/lodash": "4.14.123",
     "@types/mocha": "5.2.6",
-    "@types/mock-fs": "3.6.30",
+    "@types/mock-fs": "4.10.0",
     "@types/nock": "9.3.1",
     "@types/node": "9.6.46",
     "@types/rimraf": "2.0.2",
@@ -56,7 +56,7 @@
     "conventional-changelog-cli": "2.0.12",
     "husky": "1.3.1",
     "mocha": "6.0.2",
-    "mock-fs": "4.8.0",
+    "mock-fs": "4.12.0",
     "nock": "10.0.6",
     "nyc": "13.3.0",
     "rimraf": "2.6.3",