fix(deps): update dependency mathjs to v9 (#537)

Author: renovate-bot

cloud-language/snippets/package.json

@@ -16,7 +16,7 @@
   },
   "dependencies": {
     "@google-cloud/automl": "^2.0.0",
-    "mathjs": "^8.0.0",
+    "mathjs": "^9.0.0",
     "@google-cloud/language": "^4.2.1",
     "@google-cloud/storage": "^5.0.0",
     "yargs": "^16.0.0"