No target validator set | Spring Boot Application on Google App Engine

The example seems to have problem. When starting the app on GAE an error like that is printed. Caused by "no target validator set". On local google app engine it is working. Any help?

[s~hsr-cloud-solutions-work/20180511t100939.409639534574068310].: 2018-05-11 08:12:19.222 WARN 1 --- [RequestD8018BA4] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'cxfServletRegistration' defined in class path resource [org/apache/cxf/spring/boot/autoconfigure/CxfAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.web.servlet.ServletRegistrationBean]: Factory method 'cxfServletRegistration' threw exception; nested exception is java.lang.IllegalStateException: No target Validator set

報告沒有提供可作為起點的儲存庫檔案或測試。請在 Google App Engine 上重現 Spring Boot 應用程式，並將其與正常運作的本機 App Engine 執行進行比較，重點關注 CXF servlet 註冊以及回報的 "No target Validator set" 啟動失敗。完成的標準是應用程式能在 Google App Engine 上成功啟動且不出現此例外。

由索引模型根據 Issue 內容生成。