fix(common): add missing CHAR/VARCHAR cases in data type parser

Author: HeartLinked

src/paimon/common/types/data_type_json_parser.cpp

@@ -470,6 +470,9 @@ Result<std::shared_ptr<arrow::DataType>> TokenParser::ParseTypeByKeyword(bool* i
             *is_blob = true;
             return arrow::large_binary();
         }
+        case Keyword::CHAR:
+        case Keyword::VARCHAR:
+           return ParseStringType<arrow::StringType>();
         case Keyword::STRING:
             return arrow::utf8();
         case Keyword::BOOLEAN: