code: @Beta
    public Builder toBuilder() {
      Builder builder = new GoogleCredential.Builder()
          .setServiceAccountPrivateKey(serviceAccountPrivateKey)
          .setServiceAccountPrivateKeyId(serviceAccountPrivateKeyId)
          .setServiceAccountId(serviceAccountId)
          .setServiceAccountProjectId(serviceAccountProjectId)
          .setServiceAccountUser(serviceAccountUser)
          .setServiceAccountScopes(serviceAccountScopes)
          .setTokenServerEncodedUrl(getTokenServerEncodedUrl())
          .setTransport(getTransport())
          .setJsonFactory(getJsonFactory())
          .setClock(getClock());
  
      builder.setClientAuthentication(getClientAuthentication());
  
      return builder;
    }
docs: {@link Beta} <br/>
  Create a builder from this credential.