code: public static CredentialOptions jsonCredentials(String jsonString) {
      return jsonCredentials(new ByteArrayInputStream(jsonString.getBytes(StandardCharsets.UTF_8)));
    }
docs: <p>
  jsonCredentials.
  </p>
  @param jsonString a {@link String} object.
  @return a {@link com.google.cloud.bigtable.config.CredentialOptions} object.