Gradle warning: variant.getOutputFile() and variant.setOutputFile() are deprecated

Building on the answer from Larry Schiefer you can change the script to something like this:

android {
    applicationVariants.all { variant ->
        variant.outputs.each { output ->
            def outputFile = output.outputFile
            if (outputFile != null && outputFile.name.endsWith('.apk')) {
                def fileName = outputFile.name.replace('.apk', "-${versionName}.apk")
                output.outputFile = new File(outputFile.parent, fileName)
            }
        }
    }
}