我创建的任务复制和FTP包

task ftp(dependsOn: "copyApk") {
    doLast {
        ant {
            taskdef(name: 'ftp',
                    classname: 'org.apache.tools.ant.taskdefs.optional.net.FTP',
                    classpath: configurations.ftpAntTask.asPath)
            ftp(server: "ftp.mydomain.com", userid: "ftp.mydomain.com|administrator", password: "adkjadfsid", remoteDir: "download") {
                fileset(dir: "E:/.../download/") {
                    include(name: "my-app.apk")
                }
            }
        }
    }
}

几年来，它一直顺利地工作着。我最近将Android Studio升级到Giraffe和包括Gradle在内的一系列其他软件包。根据Android Studio的建议，该任务的脚本已更改为以下内容：

tasks.register('ftp') {
    dependsOn "copyApk"
    doLast {
        ant {
            taskdef(name: 'ftp',
                    classname: 'org.apache.tools.ant.taskdefs.optional.net.FTP',
                    classpath: configurations.ftpAntTask.asPath)
            ftp(server: "ftp.mydomain.com", userid: "ftp.mydomain.com|administrator", password: "adkjadfsid", remoteDir: "download") {
                fileset(dir: "E:/.../download/") {
                    include(name: "my-app.apk")
                }
            }
        }
    }
}

当我运行任务时，我得到以下错误：

Cannot reference a Gradle script object from a Groovy closure as these are not supported with the configuration cache.

有问题的行是：

ant {

有人能提供一个如何解决这个问题的提示吗？