beam-sdks-testing-nexmark produces corrupt pom.xml

Steps to reproduce:

./gradlew -Prelease -Ppublishing :sdks:java:testing:nexmark:publishMavenJavaPublicationTotestPublicationLocalRepository

and if you inspect the pom you will see

   <dependency>
      <groupId>org.apache.beam</groupId>
      <artifactId>beam-sdks-java-testing-test-utils</artifactId>
...

It appears to be constructed from the directories, but this (and also load-tests) in the testing directory have their archive base name overridden: https://github.com/apache/beam/blob/master/sdks/java/testing/test-utils/build.gradle#L20

So after publication, this will result in a dependency not found error.