As a plugin developer you can use this plugin as dependency of your plugin by adding a dependency tag to your POM.
To add the latest version of this plugin as a maven dependency, use the following:
<dependency>
<groupId>io.jenkins.plugins</groupId>
<artifactId>github-pr-approval</artifactId>
<version>15.vf18c6a_886ca_4</version>
</dependency>