Invalid publication 'release': multiple artifacts with the identical extension and classifier ('aar', 'null').

[Cypher103360]

I have been following this Medium doc: Publishing Android libraries to GitHub Packages

This is build.gradle file:

import java.util.Properties

plugins {
    id("com.android.library")
    id("org.jetbrains.kotlin.android")
    id("maven-publish")
}
val getVersionName = "1.0.0"
val getArtifactId = "dynamic-map"
val githubProperties = Properties()
githubProperties.load(
    rootProject.file("github.properties").inputStream()
) // Load GitHub credentials from github.properties file

android {
    ...
}

dependencies {
   ...
}

afterEvaluate {
    val gitUsername = githubProperties.getProperty("gpr.usr")
    val gitPassword = githubProperties.getProperty("gpr.key")

    println("GitHub Username: $gitUsername")
    println("GitHub Token: $gitPassword")

    publishing {
        publications {
            create<MavenPublication>("release") {
                from(components["release"])
                groupId = "com.gaurav.kumar"
                artifactId = getArtifactId
                version = getVersionName
                artifact("$buildDir/outputs/aar/${getArtifactId}-release.aar")
            }
        }
        repositories {
            maven {
                name = "DynamicMapRepo"
                url = uri("https://maven.pkg.github.com/Cypher103360/DynamicMap")

                credentials {
                    username = gitUsername
                    password = gitPassword
                }
            }
        }
    }
}

When I try to publish the library I get this:

gaurav@gaurav-ThinkPad-E15-Gen-4:~/AndroidStudioProjects/DynamicMap$ ./gradlew publish

> Configure project :dynamic-map
GitHub Username: Cypher103360
GitHub Token: *****

> Task :dynamic-map:publishReleasePublicationToDynamicMapRepoRepository FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':dynamic-map:publishReleasePublicationToDynamicMapRepoRepository'.
> Failed to publish publication 'release' to repository 'DynamicMapRepo'
   > Invalid publication 'release': multiple artifacts with the identical extension and classifier ('aar', 'null').

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.
> Get more help at https://help.gradle.org.

BUILD FAILED in 1s
25 actionable tasks: 21 executed, 4 up-to-date

@prasad79 @up9cloud @fossabot Please help me to address this issue.