Plugin execution not covered by lifecycle configuration AppEngine

Plugin execution not covered by lifecycle configuration AppEngine

Need help with the following Eclipse m2e issue:
Plugin execution not covered by lifecycle configuration:
com.google.appengine:appengine-maven-plugin:1.8.3:endpoints_get_discovery_doc
(execution: default, phase: compile)
<plugin>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-maven-plugin</artifactId>
<version>1.8.3</version>
<configuration>
<enableJarClasses>false</enableJarClasses>
</configuration>
<executions>
**<execution>**
<goals>
<goal>endpoints_get_discovery_doc</goal>
</goals>
</execution>
</executions>
</plugin>
Any ideas? The pom.xml looks like:
https://github.com/GoogleCloudPlatform/appengine-endpoints-tictactoe-java-maven/blob/master/pom.xml