code: public Observable<SecretBundle> deleteSecretAsync(String vaultBaseUrl, String secretName) {
          return deleteSecretWithServiceResponseAsync(vaultBaseUrl, secretName).map(new Func1<ServiceResponse<SecretBundle>, SecretBundle>() {
              @Override
              public SecretBundle call(ServiceResponse<SecretBundle> response) {
                  return response.body();
              }
          });
      }
docs: Deletes a secret from a specified key vault.
  
  @param vaultBaseUrl The vault name, for example https://myvault.vault.azure.net.
  @param secretName The name of the secret.
  @return the observable to the SecretBundle object