chore(deps): bump google-gax in /packages/instrumentation-vertexai

Bumps [google-gax](https://github.com/googleapis/gax-nodejs/tree/HEAD/gax) from 4.6.1 to 5.0.3.
- [Release notes](https://github.com/googleapis/gax-nodejs/releases)
- [Changelog](https://github.com/googleapis/gax-nodejs/blob/main/gax/CHANGELOG.md)
- [Commits](https://github.com/googleapis/gax-nodejs/commits/google-gax-v5.0.3/gax)

---
updated-dependencies:
- dependency-name: google-gax
  dependency-version: 5.0.3
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

packages/instrumentation-vertexai/package.json

@@ -42,7 +42,7 @@
     "@opentelemetry/instrumentation": "^0.203.0",
     "@opentelemetry/semantic-conventions": "^1.36.0",
     "@traceloop/ai-semantic-conventions": "workspace:*",
-    "google-gax": "^4.0.0",
+    "google-gax": "^5.0.3",
     "tslib": "^2.8.1"
   },
   "devDependencies": {