It looks like the dependency has an error, try deleting the artifact in your ~/.m2 file, include this dependency in your root + core pom.xml, and try to re-download & rebuild your project.
<!-- https://mvnrepository.com/artifact/net.adamcin.oakpal/oakpal-maven-plugin -->
<dependency>
<groupId>net.adamcin.oakpal</groupId>
<artifactId>oakpal-maven-plugin</artifactId>
<version>1.5.1</version>
</dependency>
I hope this works.