Update getJaasConfig.ts

Per GCP docs this is the correct JaasConfig:

https://cloud.google.com/managed-service-for-apache-kafka/docs/quickstart-java#configure_and_run_the_application

Author: mike-pt

frontend/src/widgets/ClusterConfigForm/utils/getJaasConfig.ts

@@ -11,7 +11,7 @@ const JAAS_CONFIGS = {
   'SASL/AWS IAM': 'software.amazon.msk.auth.iam.IAMLoginModule',
   'SASL/Azure Entra':
     'org.apache.kafka.common.security.oauthbearer.OAuthBearerLoginModule',
-  'SASL/GCP IAM': 'com.google.cloud.hosted.kafka.auth.GcpLoginCallbackHandler',
+  'SASL/GCP IAM': 'org.apache.kafka.common.security.oauthbearer.OAuthBearerLoginModule',
 };
 
 type MethodName = keyof typeof JAAS_CONFIGS;