@Test
public void asMap() {

  assertThat(ApiIssuerAudienceConfig.builder().build().asMap()).isEmpty();
  ApiIssuerAudienceConfig config = ApiIssuerAudienceConfig.builder()
      .addIssuerAudiences("issuer", "aud1", "aud2")
      .build();
  assertThat(config.asMap()).containsExactly("issuer", ImmutableSet.of("aud1", "aud2"));
}