Reproducer

To reproduce, run:

mvn clean install

Output:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-javadoc-plugin:3.5.0:jar (default) on project reproducer:
Execution default of goal org.apache.maven.plugins:maven-javadoc-plugin:3.5.0:jar failed:
Unable to derive module descriptor for /.../.m2/repository/org/openrewrite/rewrite-gradle/7.38.0/rewrite-gradle-7.38.0.jar:
PluginSpec.class found in top-level directory (unnamed package not allowed in module) -> [Help 1]

Jira: https://issues.apache.org/jira/browse/MJAVADOC-747