Gradle doesn't publish artifacts

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1

I would like to publish two artifacts built from two submodules. In the parent module I’ve got the following configuration:

apply plugin: 'com.jfrog.artifactory'
apply plugin: 'maven-publish'

publishing {
    publications {
        first(MavenPublication) {
            groupId group
            version version
            artifactId 'first-lib'

            artifact("first-lib/$buildDir/libs/first-lib-${version}.jar")
        }
        second(MavenPublication) {
            groupId group
            version version
            artifactId 'second-lib'

            artifact("second-lib/$buildDir/libs/second-lib-${version}.jar")
        }
    }
}

artifactory {
    contextUrl = 'http://host/artifactory'
    publish {
        repository {
            repoKey = 'repoKey'
            username = 'user'
            password = 'pass'
        }
    }
}

However, nothing get’s published when I run gradle artifactoryPublish.

Thank you for any ideas!

P.S. Gradle version is 4.6, artifactory plugin version 4.6.2