--result-dir enabled in TLT
This pull request **introduces 1 alert** when merging 340f7482b74ee14f376e15450762888c0536e201 into 16055d86b0be550b87ee5d327e351a1562ce7eb2 - [view on LGTM.com](https://lgtm.com/projects/g/NVIDIA/NeMo/rev/pr-2be8828844b45e4c518c59e6cf4c908a99fc228e)

**new alerts:**

* 1 for Unused import This pull request **introduces 1 alert** when merging b7e4358cd6bd6e4a2428749fcbf569d393fdfefd into 1c24a5d35a9680b7436f505a8e69dc8f8373f3c2 - [view on LGTM.com](https://lgtm.com/projects/g/NVIDIA/NeMo/rev/pr-29672ebec67da7b0117c1d17394c488f86248496)

**new alerts:**

* 1 for Unused import
Modifications enabling TLT text classification train to use ExpManager

- [x] added postfix to ckpt callback structured config + its handling
- [x] minimally polished logic for explicit_log_dir
- [x] minor polish of names
- [x] Bumped versions in requirements: omegaconf, hydra to make Optional[List]] work
- [x] Bumped version of PTL to 1.1 to enable CheckpointConnector overload in TLT
 