docs: protected boolean validateFixedUrl(final SpecNode specNode, final Set<String> processedFixedUrls) {
          boolean valid = true;
  
          if (!ProcessorConstants.VALID_FIXED_URL_PATTERN.matcher(specNode.getFixedUrl()).matches()) {
              log.error(format(ProcessorConstants.ERROR_FIXED_URL_NOT_VALID, specNode.getLineNumber(), specNode.getText()));
              valid = false;
          } else if (processedFixedUrls.contains(specNode.getFixedUrl())) {
              log.error(format(ProcessorConstants.ERROR_FIXED_URL_NOT_UNIQUE, specNode.getLineNumber(), specNode.getFixedUrl(),
                      specNode.getText()));
              valid = false;
          }
  
          return valid;
      }