fix the bug in line 251: 1、 del the additional blank 2、correct the spell error of "new_vocab_size"
* initial commit for libriheavy * Data prepare pipeline * Fix train.py * Fix decode.py * Add results * minor fixes * black * black * Incorporate PR https://github.com/k2-fsa/icefall/pull/1269 --------- Co-authored-by: zr_jin <peter.jin.cn@gmail.com>