chore(deps): update dependency sinon to v6

Author: renovate-bot

package-lock.json

@@ -64,7 +64,7 @@
     "prettier": "1.12.1",
     "rimraf": "^2.5.4",
     "semantic-release": "^15.4.0",
-    "sinon": "^5.0.7",
+    "sinon": "^6.0.0",
     "source-map-support": "^0.5.5",
     "tslint": "^5.10.0",
     "typedoc": "^0.11.0",