in artifactregistry-gradle-plugin/src/main/java/com/google/cloud/artifactregistry/gradle/plugin/ArtifactRegistryGradlePlugin.java [142:148]
private void modifyProject(Project p, @Nullable ArtifactRegistryPasswordCredentials crd) {
p.getRepositories().forEach(r -> configureArtifactRegistryRepository(r, crd));
final PublishingExtension publishingExtension = p.getExtensions().findByType(PublishingExtension.class);
if (publishingExtension != null) {
publishingExtension.getRepositories().forEach(r -> configureArtifactRegistryRepository(r, crd));
}
}