chore(deps): update dependency org.hibernate:hibernate-core to v5.4.31.final (GoogleCloudPlatform#5157)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.hibernate:hibernate-core](http://hibernate.org/orm) ([source](https://togithub.com/hibernate/hibernate-orm)) | `5.4.30.Final` -> `5.4.31.Final` | [![age](https://badges.renovateapi.com/packages/maven/org.hibernate:hibernate-core/5.4.31.Final/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/org.hibernate:hibernate-core/5.4.31.Final/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/org.hibernate:hibernate-core/5.4.31.Final/compatibility-slim/5.4.30.Final)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/org.hibernate:hibernate-core/5.4.31.Final/confidence-slim/5.4.30.Final)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>hibernate/hibernate-orm</summary>

### [`v5.4.31.Final`](https://togithub.com/hibernate/hibernate-orm/compare/5.4.30...5.4.31)

[Compare Source](https://togithub.com/hibernate/hibernate-orm/compare/5.4.30...5.4.31)

</details>

---

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Author: renovate-bot

spanner/hibernate/pom.xml

@@ -44,7 +44,7 @@
     <dependency>
       <groupId>org.hibernate</groupId>
       <artifactId>hibernate-core</artifactId>
-      <version>5.4.30.Final</version>
+      <version>5.4.31.Final</version>
     </dependency>
   </dependencies>
   <!-- [END spanner_hibernate_dependencies] -->