fix(deps): update dependency google-gax to v4.2.1 (#1989)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [google-gax](https://togithub.com/googleapis/gax-nodejs) ([source](https://togithub.com/googleapis/gax-nodejs/tree/HEAD/gax)) | [`4.2.0` -> `4.2.1`](https://renovatebot.com/diffs/npm/google-gax/4.2.0/4.2.1) | [![age](https://developer.mend.io/api/mc/badges/age/npm/google-gax/4.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/npm/google-gax/4.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/npm/google-gax/4.2.0/4.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/google-gax/4.2.0/4.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>googleapis/gax-nodejs (google-gax)</summary>

### [`v4.2.1`](https://togithub.com/googleapis/gax-nodejs/compare/v4.2.0...ae37986ddc9f6c822ff557248cdf68529931abc6)

[Compare Source](https://togithub.com/googleapis/gax-nodejs/compare/v4.2.0...ae37986ddc9f6c822ff557248cdf68529931abc6)

</details>

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package.json

@@ -65,7 +65,7 @@
     "events-intercept": "^2.0.0",
     "extend": "^3.0.2",
     "google-auth-library": "^9.0.0",
-    "google-gax": "4.2.0",
+    "google-gax": "4.2.1",
     "grpc-gcp": "^1.0.0",
     "is": "^3.2.1",
     "lodash.snakecase": "^4.1.1",