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>com.amazon.jenkins.fleet</groupId>
<artifactId>ec2-fleet</artifactId>
<version>4.3.0.549.vf2a_da_a_d19b_5e</version>
</dependency>