Update tested versions for org.apache.activemq:activemq-client

Author: actions-user

metadata/org.apache.activemq/activemq-client/index.json

@@ -15,7 +15,8 @@
       "6.1.6",
       "6.1.7",
       "6.1.8",
-      "6.2.0"
+      "6.2.0",
+      "6.2.1"
     ]
   },
   {