How to add images to output with AsciiDoctor Gradle plugin

To add images to output with AsciiDoctor Gradle plugin

add the following configuration to your `build.gradle` file:

asciidoctor {
    resources {
        from (sourceDir) {
            include "**/*.png"
        }
    }
}

Reference:
https://github.com/asciidoctor/asciidoctor-gradle-plugin