chore(deps): update dependency documentation to v9.2.1

Author: renovate-bot

package.json

@@ -62,7 +62,7 @@
     "chai": "4.2.0",
     "chai-as-promised": "7.1.1",
     "codecov": "3.1.0",
-    "documentation": "9.0.0-alpha.1",
+    "documentation": "9.2.1",
     "husky": "1.1.4",
     "nock": "10.0.2",
     "eslint": "5.8.0",