Dependabot Gradle - configuration

Hi,

I am using GitHub - dependabot/dependabot-script: A simple script that demonstrates how to use Dependabot Core to try out automating our gradle dependencies. I have got a simple POC working. But when I try to mimic our production gradle code which uses dependency configurations, it does not recognise my dependencies.

// Works
dependencies {
    testImplementation group: 'junit', name: 'junit', version: '4.8'
    implementation group: 'com.google.guava', name: 'guava', version: '25.1-jre'
}
// Doesnt work
dependencies {
    implementation configurations.guava
    testImplementation configurations.junit
    guava (
            [group: 'com.google.guava', name: 'guava', version: '25.1-jre']
    )
    junit (
            [group: 'junit', name: 'junit', version: '4.8']
    )
}

I dont receive any error, it just doesnt seem to find the dependencies.

Also, not sure if this is an issue in our code or not, but it doesnt seem like dependabot can resolve variables that are in a map. I have tried several approaches

ext {
    versions = [
            'guava'                   : '25.1-jre', // latest version is 30.1.1-jre
            'junit4'                  : '4.8',
    ]
    junitVersion = '4.8'
    guavaVersion = '25.1-jre' // latest version is 30.1.1-jre
}


dependencies {
    // Use JUnit test framework.
    // Doesnt work
    //testImplementation group: 'junit', name: 'junit', version: versions.junit4
    // Doesnt work
    //testImplementation group: 'junit', name: 'junit', version: junitVersion
    // Works
    //testImplementation group: 'junit', name: 'junit', version: '4.8'
    // Also works
    //testImplementation "junit:junit:${junitVersion}"
    // Also works
    testImplementation group: 'junit', name: 'junit', version: "$junitVersion"
    // Doesnt work
    //testImplementation group: 'junit', name: 'junit', version: "$versions.junit4"