test(deps): update dependency org.mockito:mockito-core to v4.3.1 (#1660)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.mockito:mockito-core](https://togithub.com/mockito/mockito) | `4.3.0` -> `4.3.1` | [![age](https://badges.renovateapi.com/packages/maven/org.mockito:mockito-core/4.3.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/org.mockito:mockito-core/4.3.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/org.mockito:mockito-core/4.3.1/compatibility-slim/4.3.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/org.mockito:mockito-core/4.3.1/confidence-slim/4.3.0)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>mockito/mockito</summary>

### [`v4.3.1`](https://togithub.com/mockito/mockito/releases/v4.3.1)

[Compare Source](https://togithub.com/mockito/mockito/compare/v4.3.0...v4.3.1)

<sup><sup>*Changelog generated by [Shipkit Changelog Gradle Plugin](https://togithub.com/shipkit/shipkit-changelog)*</sup></sup>

##### 4.3.1

-   2022-01-25 - [1 commit(s)](https://togithub.com/mockito/mockito/compare/v4.3.0...v4.3.1) by Stefano Cordio
-   Add `mockito-core` to the BOM [(#&#8203;2550)](https://togithub.com/mockito/mockito/pull/2550)

</details>

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google-cloud-spanner/pom.xml

@@ -288,7 +288,7 @@
     <dependency>
       <groupId>org.mockito</groupId>
       <artifactId>mockito-core</artifactId>
-      <version>4.3.0</version>
+      <version>4.3.1</version>
       <scope>test</scope>
     </dependency>
     <dependency>