[fix][cli] Remove defaultValue of tenant/namespace for CmdFunctions (#22764)

(cherry picked from commit 951eb518f7792f42df6bb343784ab5ae2f8bf32d)
diff --git a/pulsar-client-tools/src/main/java/org/apache/pulsar/admin/cli/CmdFunctions.java b/pulsar-client-tools/src/main/java/org/apache/pulsar/admin/cli/CmdFunctions.java
index 5e80c16..4c7e058 100644
--- a/pulsar-client-tools/src/main/java/org/apache/pulsar/admin/cli/CmdFunctions.java
+++ b/pulsar-client-tools/src/main/java/org/apache/pulsar/admin/cli/CmdFunctions.java
@@ -100,12 +100,10 @@
      */
     @Getter
     abstract class NamespaceCommand extends BaseCommand {
-        @Option(names = "--tenant", description = "The tenant of a Pulsar Function",
-                defaultValue = PUBLIC_TENANT)
+        @Option(names = "--tenant", description = "The tenant of a Pulsar Function")
         protected String tenant;
 
-        @Option(names = "--namespace", description = "The namespace of a Pulsar Function",
-                defaultValue = DEFAULT_NAMESPACE)
+        @Option(names = "--namespace", description = "The namespace of a Pulsar Function")
         protected String namespace;
     }
 
@@ -117,12 +115,10 @@
         @Option(names = "--fqfn", description = "The Fully Qualified Function Name (FQFN) for the function")
         protected String fqfn;
 
-        @Option(names = "--tenant", description = "The tenant of a Pulsar Function",
-                defaultValue = PUBLIC_TENANT)
+        @Option(names = "--tenant", description = "The tenant of a Pulsar Function")
         protected String tenant;
 
-        @Option(names = "--namespace", description = "The namespace of a Pulsar Function",
-                defaultValue = DEFAULT_NAMESPACE)
+        @Option(names = "--namespace", description = "The namespace of a Pulsar Function")
         protected String namespace;
 
         @Option(names = "--name", description = "The name of a Pulsar Function")
@@ -170,11 +166,9 @@
         @Option(names = "--fqfn", description = "The Fully Qualified Function Name (FQFN) for the function"
                 + " #Java, Python")
         protected String fqfn;
-        @Option(names = "--tenant", description = "The tenant of a Pulsar Function #Java, Python, Go",
-                defaultValue = PUBLIC_TENANT)
+        @Option(names = "--tenant", description = "The tenant of a Pulsar Function #Java, Python, Go")
         protected String tenant;
-        @Option(names = "--namespace", description = "The namespace of a Pulsar Function #Java, Python, Go",
-                defaultValue = DEFAULT_NAMESPACE)
+        @Option(names = "--namespace", description = "The namespace of a Pulsar Function #Java, Python, Go")
         protected String namespace;
         @Option(names = "--name", description = "The name of a Pulsar Function #Java, Python, Go")
         protected String functionName;