Fix: seemingly equal ClientConfigurationData's objects end up not bei…

…ng equal (apache#10091)

* fixed equals for the ClientConfigurationData (found while fixing tests in pulsar-adapters repo)

* added test/repro

* CR feedback

pulsar-client/src/main/java/org/apache/pulsar/client/impl/conf/ClientConfigurationData.java

@@ -106,7 +106,7 @@ public class ClientConfigurationData implements Serializable, Cloneable {
 
     public Authentication getAuthentication() {
         if (authentication == null) {
-            this.authentication = new AuthenticationDisabled();
+            this.authentication = AuthenticationDisabled.INSTANCE;
         }
         return authentication;
     }

pulsar-client/src/test/java/org/apache/pulsar/client/impl/conf/ConfigurationDataUtilsTest.java

@@ -185,4 +185,16 @@ public void testLoadSecretParams() {
             Assert.fail();
         }
     }
+
+    @Test
+    public void testEquals() {
+        ClientConfigurationData confData1 = new ClientConfigurationData();
+        confData1.setServiceUrl("pulsar://unknown:6650");
+
+        ClientConfigurationData confData2 = new ClientConfigurationData();
+        confData2.setServiceUrl("pulsar://unknown:6650");
+
+        assertEquals(confData1, confData2);
+        assertEquals(confData1.hashCode(), confData2.hashCode());
+    }
 }