Add bounds check for postprocess_utils.py abbr_dispose() (#2209)

"/Users/{USER}/.pyenv/versions/funasr_usage/lib/python3.12/site-packages/funasr/utils/postprocess_utils.py", line 127, in abbr_dispose
    end = time_stamp[ts_nums[num]][1]
          ~~~~~~~~~~^^^^^^^^^^^^^^
IndexError: list index out of range