Bump gson from 2.8.6 to 2.8.9 in /api

Bumps [gson](https://github.com/google/gson) from 2.8.6 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-2.8.6...gson-parent-2.8.9)

---
updated-dependencies:
- dependency-name: com.google.code.gson:gson
  dependency-type: direct:production
...

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

Author: dependabot[bot]

api/pom.xml

@@ -272,7 +272,7 @@
         <gson-fire-version>1.8.5</gson-fire-version>
         <swagger-core-version>1.6.2</swagger-core-version>
         <okhttp-version>4.9.1</okhttp-version>
-        <gson-version>2.8.6</gson-version>
+        <gson-version>2.8.9</gson-version>
         <commons-lang3-version>3.11</commons-lang3-version>
         <javax-annotation-version>1.3.2</javax-annotation-version>
         <junit-version>4.13.1</junit-version>