Bump gson from 2.2.4 to 2.8.9

Bumps [gson](https://github.com/google/gson) from 2.2.4 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-2.2.4...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]

pom.xml

@@ -18,7 +18,7 @@
         <hbase.version>2.1.0</hbase.version>
         <mysql-connector.version>8.0.21</mysql-connector.version>
         <flink.cdc.version>2.2.0</flink.cdc.version>
-        <gson.version>2.2.4</gson.version>
+        <gson.version>2.8.9</gson.version>
         <lettuce.version>6.1.3.RELEASE</lettuce.version>
         <common.io>2.7</common.io>
         <starrocks.version>1.2.2_flink-1.15_2.12</starrocks.version>