docs: private static void prepImportsList(List<SymbolTable> importsList,
                                          IonReader reader,
                                          IonCatalog catalog)
      {
          assert IMPORTS.equals(reader.getFieldName());
  
          reader.stepIn();
          IonType t;
          while ((t = reader.next()) != null)
          {
              if (!reader.isNullValue() && t == IonType.STRUCT)
              {
                  SymbolTable importedTable = readOneImport(reader, catalog);
  
                  if (importedTable != null)
                  {
                      importsList.add(importedTable);
                  }
              }
          }
          reader.stepOut();
      }