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>pipeline-keepenv-step</artifactId>
<version>1.17.v407d68513ea_6</version>
</dependency>