update config to add argument:ser_class_dict_path

[hongziqi]

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Motivation

replace hardcoded paths with the ser_class_dict_path configuration parameter, enhancing flexibility and maintainability.

Test Plan

python tools/infer/text/predict_ser.py --rec_algorithm SVTR_PPOCRv3_CH --det_algorithm DB++  --image_dir configs/kie/vi_layoutxlm/example.jpg --rec_char_dict_path mindocr/utils/dict/ch_dict.txt  --ser_class_dict_path mindocr/utils/dict/class_list_xfun.txt

[jiahaochen666]

lgtm