Bump transformers in /examples/pytorch/deepspeed-demo

Bumps [transformers](https://github.com/huggingface/transformers) from 4.5.1 to 4.38.0.
- [Release notes](https://github.com/huggingface/transformers/releases)
- [Commits](huggingface/transformers@v4.5.1...v4.38.0)

---
updated-dependencies:
- dependency-name: transformers
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

examples/pytorch/deepspeed-demo/requirements.txt

@@ -1,5 +1,5 @@
 datasets==1.13.3
-transformers==4.5.1
+transformers==4.38.0
 fire==0.4.0
 pytz==2021.1
 loguru==0.5.3