exclude com.google.gerrit.extensions from coverage
exclude com.google.gerrit.extensions from coverage

- these files are just a plain copy of gerrit source

sstafford/gerrit-rest-java-client,uwolfer/gerrit-rest-java-client,sstafford/gerrit-rest-java-client,vogellacompany/gerrit-rest-java-client,vogellacompany/gerrit-rest-java-client,uwolfer/gerrit-rest-java-client