[Enhance] Add training time for distill sd

[okotaku]

Results (Optional)

Training Speed

Environment:

• A6000 Single GPU
• nvcr.io/nvidia/pytorch:23.07-py3

Settings:

• 1k iterations training, (validation 4 images / 100 iterations)
• LoRA (rank=8) / DreamBooth

Model	total time
SDV1.5	16 m 39 s
Small SD	11 m 57 s
Tiny SD	11 m 17 s

Checklist

Before PR:

• Pre-commit or other linting tools are used to fix the potential lint issues.
• Bug fixes are fully covered by unit tests, the case that causes the bug should be added in the unit tests.
• The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
• The documentation has been modified accordingly, like docstring or example tutorials.