FE: Auth: Add GCP IAM missing enums (#1075)

Author: Haarolean

frontend/src/widgets/ClusterConfigForm/schema.ts

@@ -167,6 +167,7 @@ const authSchema = lazy((value) => {
           'SASL/LDAP',
           'SASL/AWS IAM',
           'SASL/Azure Entra',
+          'SASL/GCP IAM',
           'mTLS',
         ]),
       securityProtocol: string()
@@ -183,6 +184,7 @@ const authSchema = lazy((value) => {
               'SASL/LDAP',
               'SASL/AWS IAM',
               'SASL/Azure Entra',
+              'SASL/GCP IAM',
             ].includes(v);
           },
           then: (schema) => schema.required('required field'),