[Bugfix] fix text generator as input

[BeautyyuYanli]

When the input is a text generator like

to_generate = [
    "收到好友从远方寄来的生日礼物",
    "那份意外的惊喜与深深的祝福",
    "让我心中充满了甜蜜的快乐",
    "笑容如花儿般绽放。",
]
def text_generator():
    for i in to_generate:
        yield i

for i, j in enumerate(cosyvoice.inference_instruct2(text_generator(), "用温柔的语音说", prompt_speech_16k, stream=False)):
    torchaudio.save('instruct_{}.wav'.format(i), j['tts_speech'], cosyvoice.sample_rate)

the text normalizer behavior is wrong.

[aluminumbox]

这样的修改的结果就是generator被当成了普通文本处理，虽然是可以正常前端处理，但generator的目的是双向流式推理，不应该这样修改