Plugin return an error on gradle 5.1.1

[VovaStelmashchuk]

I include your plugin to project like a:
apply from: 'https://raw.github.com/Vorlonsoft/EasyDokkaPlugin/master/dokka.gradle'
All works fine. But I update my project to gradle 5.1.1. Plugin return the errors.

My project

Logs from ci