chore(main): release 4.0.0 (#626)

* chore(main): release 4.0.0

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>
Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: sofisl <55454395+sofisl@users.noreply.github.com>

asset/snippets/package.json

@@ -15,7 +15,7 @@
     "test": "mocha --timeout 600000"
   },
   "dependencies": {
-    "@google-cloud/asset": "^3.23.1",
+    "@google-cloud/asset": "^4.0.0",
     "@google-cloud/bigquery": "^6.0.0",
     "@google-cloud/compute": "^3.0.0",
     "@google-cloud/storage": "^6.0.0",