deps: update dependency org.threeten:threetenbp to v1.6.1 (#902)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.threeten:threetenbp](https://www.threeten.org/threetenbp) ([source](https://togithub.com/ThreeTen/threetenbp)) | `1.6.0` -> `1.6.1` | [![age](https://badges.renovateapi.com/packages/maven/org.threeten:threetenbp/1.6.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/org.threeten:threetenbp/1.6.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/org.threeten:threetenbp/1.6.1/compatibility-slim/1.6.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/org.threeten:threetenbp/1.6.1/confidence-slim/1.6.0)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>ThreeTen/threetenbp</summary>

### [`v1.6.1`](https://togithub.com/ThreeTen/threetenbp/releases/tag/v1.6.1)

[Compare Source](https://togithub.com/ThreeTen/threetenbp/compare/v1.6.0...v1.6.1)

See the [change notes](https://www.threeten.org/threetenbp/changes-report.html) for more information.

</details>

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Author: renovate-bot

java-core/pom.xml

@@ -167,7 +167,7 @@
     <truth.version>1.1.3</truth.version>
     <easymock.version>4.3</easymock.version>
     <findbugs.version>3.0.2</findbugs.version>
-    <threetenbp.version>1.6.0</threetenbp.version>
+    <threetenbp.version>1.6.1</threetenbp.version>
     <objenesis.version>3.3</objenesis.version>
     <errorprone.version>2.15.0</errorprone.version>
     <gson.version>2.9.1</gson.version>