dependabot security fixes

java/failover/pom.xml

@@ -38,7 +38,7 @@
     <dependency>
       <groupId>com.google.code.gson</groupId>
       <artifactId>gson</artifactId>
-      <version>2.8.6</version>
+      <version>2.8.9</version>
     </dependency>
   </dependencies>