update the "-cluster" parameter in the delete-cluster-metadata comman…

…d to "--cluster" (apache#9487)

* update the "-cluster" parameter in the delete-cluster-metadata command to "--cluster"

### Motivation


* update the **-cluster** parameter in the delete-cluster-metadata command to **--cluster**. *

### Modifications

* update the **-cluster** parameter in the delete-cluster-metadata command to **--cluster**. *

* keeping the old way, and add the new parameter --cluster

pulsar-broker/src/main/java/org/apache/pulsar/PulsarClusterMetadataTeardown.java

@@ -55,7 +55,7 @@ private static class Arguments {
         }, description = "Local zookeeper session timeout ms")
         private int zkSessionTimeoutMillis = 30000;
 
-        @Parameter(names = { "-c", "-cluster" }, description = "Cluster name")
+        @Parameter(names = { "-c", "-cluster", "--cluster" }, description = "Cluster name")
         private String cluster;
 
         @Parameter(names = { "-cs", "--configuration-store" }, description = "Configuration Store connection string")