createMissingPublications
Creates missing publications based on the plugins being applied and the tasks found in the project.
Some plugins (like the Kotlin multiplatform plugin) create publications automatically but others do not (like the Kotlin JVM one).
createMissingPublications makes sure a publication is created for this module and that this publication contains source and javadoc jars.
The added javadoc jar is empty and only required to pass the Maven Central checks.
Parameters
docUrl
an optional link to write inside the empty javadoc jar for users looking for more information.