Remove experimental automodel
This pull request **introduces 1 alert** when merging 9c18170f1ed653b80bdf62dc30c810dbf3e5b87f into 48620bb1369dc72dcac7b9a4e75b113f1cc55d36 - [view on LGTM.com](https://lgtm.com/projects/g/NVIDIA/NeMo/rev/pr-29b3095947becb5ca10111ca89fa4e93061b71fb)

**new alerts:**

* 1 for Unused import is this a fix? should we send this to v1.0.0b2 as well? > is this a fix? should we send this to v1.0.0b2 as well?

both v1.0.0b2 and main are Ok, it's not a bug just removing these to avoid confusion for users that any model from get_lm() works with all NLP tasks. changed base to v1.0.0b2
