feat: upgrade multiple dependencies with Snyk

Snyk has created this PR to upgrade:
  - c8 from 7.14.0 to 10.1.2.
    See this package in npm: https://www.npmjs.com/package/c8
  - gaxios from 5.1.3 to 6.7.1.
    See this package in npm: https://www.npmjs.com/package/gaxios
  - smee-client from 1.2.5 to 2.0.3.
    See this package in npm: https://www.npmjs.com/package/smee-client

See this project in Snyk:
https://app.snyk.io/org/cachiman/project/0373eaaa-842b-44c6-8d77-7132afd4ea46?utm_source=github&utm_medium=referral&page=upgrade-pr

package.json

@@ -14,9 +14,9 @@
     "generate-bot": "node ./packages/generate-bot/run.js"
   },
   "devDependencies": {
-    "c8": "^7.1.0",
-    "gaxios": "^5.0.0",
-    "smee-client": "^1.1.0",
+    "c8": "^10.1.2",
+    "gaxios": "^6.7.1",
+    "smee-client": "^2.0.3",
     "@google-cloud/mono-repo-publish": "^1.0.0"
   }
 }