docs: @Override
      public ClientHttpResponse intercept(
              HttpRequest req, byte[] body, ClientHttpRequestExecution execution) throws IOException {
          Assert.notNull(propertyResolver);
          Assert.notNull(id);
  
          try {
              String authString = getOAuthAuthString(req);
              req.getHeaders().add(Headers.Authorization.name(), authString);
          } catch (Exception e) {
              throw new IOException("Error building OAuth header", e);
          }
  
          return execution.execute(req, body);
      }