chore(package): update sinon to version 9.0.1

Closes #17

Author: greenkeeper[bot]

package.json

@@ -43,7 +43,7 @@
     "mocha-lcov-reporter": "^1.3.0",
     "nyc": "^14.1.1",
     "semantic-release": "^15.13.19",
-    "sinon": "^7.3.2",
+    "sinon": "^9.0.1",
     "sinon-chai": "^3.2.0"
   },
   "repository": {