Bump aiohttp from 3.9.0 to 3.9.4 in /examples/research_projects/decision_transformer (#31317)

Bump aiohttp in /examples/research_projects/decision_transformer

Bumps [aiohttp](https://github.com/aio-libs/aiohttp) from 3.9.0 to 3.9.4.
- [Release notes](https://github.com/aio-libs/aiohttp/releases)
- [Changelog](https://github.com/aio-libs/aiohttp/blob/master/CHANGES.rst)
- [Commits](https://github.com/aio-libs/aiohttp/compare/v3.9.0...v3.9.4

)

---
updated-dependencies:
- dependency-name: aiohttp
  dependency-type: direct:production
...
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examples/research_projects/decision_transformer/requirements.txt

 absl-py==1.0.0
-aiohttp==3.9.0
+aiohttp==3.9.4
 aiosignal==1.2.0
 alembic==1.7.7
 appdirs==1.4.4