deps: update google.core.version to v2.8.16 (#810)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.cloud:google-cloud-core](https://togithub.com/googleapis/java-core) | `2.8.15` -> `2.8.16` | [![age](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core/2.8.16/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core/2.8.16/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core/2.8.16/compatibility-slim/2.8.15)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core/2.8.16/confidence-slim/2.8.15)](https://docs.renovatebot.com/merge-confidence/) |
| [com.google.cloud:google-cloud-core-bom](https://togithub.com/googleapis/java-core) | `2.8.15` -> `2.8.16` | [![age](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core-bom/2.8.16/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core-bom/2.8.16/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core-bom/2.8.16/compatibility-slim/2.8.15)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-core-bom/2.8.16/confidence-slim/2.8.15)](https://docs.renovatebot.com/merge-confidence/) |

---

### Release Notes

<details>
<summary>googleapis/java-core</summary>

### [`v2.8.16`](https://togithub.com/googleapis/java-core/blob/HEAD/CHANGELOG.md#&#8203;2816-httpsgithubcomgoogleapisjava-corecomparev2815v2816-2022-09-26)

##### Dependencies

-   Update dependency org.threeten:threetenbp to v1.6.2 ([#&#8203;929](https://togithub.com/googleapis/java-core/issues/929)) ([2f797f9](https://togithub.com/googleapis/java-core/commit/2f797f990eacc112dd982e7a8f9155bc229b7bf3))

</details>

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Author: renovate-bot

first-party-dependencies/pom.xml

@@ -63,7 +63,7 @@
     <protobuf.version>3.21.6</protobuf.version>
     <google.api-common.version>2.2.1</google.api-common.version>
     <google.common-protos.version>2.9.3</google.common-protos.version>
-    <google.core.version>2.8.15</google.core.version>
+    <google.core.version>2.8.16</google.core.version>
     <google.auth.version>1.11.0</google.auth.version>
     <google.http-client.version>1.42.2</google.http-client.version>
     <google.oauth-client.version>1.34.1</google.oauth-client.version>