Javadoc errors on JDK 11+

[codefromthecrypt]

Some things on internet suggest solution is to move to 13, but #2893

Exit code: 1 - error: --add-modules ALL-MODULE-PATH can only be used when compiling the unnamed module

Command line was: /Library/Java/JavaVirtualMachines/jdk-11.0.3.jdk/Contents/Home/bin/javadoc @options @argfile

Refer to the generated Javadoc files in '/Users/acole/oss/zipkin-reporter-java/metrics-micrometer/target/apidocs' dir.

org.apache.maven.reporting.MavenReportException: 
Exit code: 1 - error: --add-modules ALL-MODULE-PATH can only be used when compiling the unnamed module

Command line was: /Library/Java/JavaVirtualMachines/jdk-11.0.3.jdk/Contents/Home/bin/javadoc @options @argfile