Bump gson from 2.8.8 to 2.8.9

Bumps [gson](https://github.com/google/gson) from 2.8.8 to 2.8.9.
- [Release notes](https://github.com/google/gson/releases)
- [Changelog](https://github.com/google/gson/blob/master/CHANGELOG.md)
- [Commits](google/gson@gson-parent-2.8.8...gson-parent-2.8.9)

---
updated-dependencies:
- dependency-name: com.google.code.gson:gson
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pom.xml

@@ -49,7 +49,7 @@
     <junit.version>4.13</junit.version>
     <bucket4j.version>6.3.0</bucket4j.version>
     <bouncycastle.version>1.69</bouncycastle.version>
-    <gson.version>2.8.8</gson.version>
+    <gson.version>2.8.9</gson.version>
     <jsr305.version>3.0.2</jsr305.version>
     <okhttp3.version>4.9.1</okhttp3.version>
     <swagger-core.version>1.6.3</swagger-core.version>