fix: update dependency net.java.dev.jna:jna to v5.18.1 (#544)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [net.java.dev.jna:jna](https://redirect.github.com/java-native-access/jna) | `5.18.0` -> `5.18.1` | [![age](https://developer.mend.io/api/mc/badges/age/maven/net.java.dev.jna:jna/5.18.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/net.java.dev.jna:jna/5.18.0/5.18.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>java-native-access/jna (net.java.dev.jna:jna)</summary>

### [`v5.18.1`](https://redirect.github.com/java-native-access/jna/blob/HEAD/CHANGES.md#Release-5181)

[Compare Source](https://redirect.github.com/java-native-access/jna/compare/5.18.0...5.18.1)

\==============

## Bug Fixes

- [#&#8203;1686](https://redirect.github.com/java-native-access/jna/issues/1686): Fix `sortFields` race condition while getting fields - [@&#8203;bendk](https://redirect.github.com/bendk).

</details>

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Author: renovate-bot

spannerlib/wrappers/spannerlib-java/pom.xml

@@ -39,7 +39,7 @@
     <dependency>
       <groupId>net.java.dev.jna</groupId>
       <artifactId>jna</artifactId>
-      <version>5.18.0</version>
+      <version>5.18.1</version>
     </dependency>
 
     <!-- Test dependencies -->