fix task.py with no dest_sample_rate task; fix bug in train and infer

mengzhe.cmz

2023-04-12 1ad439f96b8cdbca98ee95b886d692dfa20e85ce

 docs/index.rst

@@ -23,6 +23,7 @@
   :caption: ModelScope:

   ./modelscope_models.md
   ./modelscope_usages.md

Indices and tables
==================