HDFS-16947. RBF NamenodeHeartbeatService to report error for not being able to register namenode in state store (#5470)

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/NamenodeHeartbeatService.java

@@ -317,11 +317,8 @@ public class NamenodeHeartbeatService extends PeriodicService {
       if (!resolver.registerNamenode(report)) {
         LOG.warn("Cannot register namenode {}", report);
       }
-    } catch (IOException e) {
-      LOG.info("Cannot register namenode in the State Store");
-    } catch (Exception ex) {
-      LOG.error("Unhandled exception updating NN registration for {}",
-          getNamenodeDesc(), ex);
+    } catch (Exception e) {
+      LOG.error("Cannot register namenode {} in the State Store", getNamenodeDesc(), e);
     }
   }