Only disable autoconfiguration if auth is also set

Author: Vlatombe

src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesFactoryAdapter.java

@@ -107,8 +107,9 @@ public KubernetesClient createClient() throws KubernetesAuthException {
             LOGGER.log(FINE, "Autoconfiguring Kubernetes client");
             builder = new ConfigBuilder(Config.autoConfigure(null));
         } else {
-            // Using Config.empty() disables autoconfiguration
-            builder = new ConfigBuilder(Config.empty()).withMasterUrl(serviceAddress);
+            // Using Config.empty() disables autoconfiguration when both serviceAddress and auth are set
+            builder = auth == null ? new ConfigBuilder() : new ConfigBuilder(Config.empty());
+            builder = builder.withMasterUrl(serviceAddress);
         }
 
         if (auth != null) {