chore(package): update sinon to version 9.0.0

Closes #58

Author: greenkeeper[bot]

package.json

@@ -44,7 +44,7 @@
         "mocha": "^6.2.2",
         "prettier": "^1.18.2",
         "pretty-quick": "^2.0.0",
-        "sinon": "^7.5.0",
+        "sinon": "^9.0.0",
         "sinon-chai": "^3.3.0",
         "tslint": "5.20.0",
         "tslint-config-prettier": "^1.18.0"