Update Spring Cloud Data Flow dependency version to `1.2.1.RELEASE`
Update Spring Cloud Data Flow dependency version to `1.2.1.RELEASE`

spring-cloud/spring-cloud-dataflow-server-cloudfoundry,spring-cloud/spring-cloud-dataflow-admin-cloudfoundry,spring-cloud/spring-cloud-dataflow-admin-cloudfoundry,spring-cloud/spring-cloud-dataflow-admin-cloudfoundry,spring-cloud/spring-cloud-dataflow-server-cloudfoundry,spring-cloud/spring-cloud-dataflow-server-cloudfoundry