Bump urllib3 from 1.26.17 to 1.26.18 in /examples/research_projects/decision_transformer (#26889)

Bump urllib3 in /examples/research_projects/decision_transformer

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.26.17 to 1.26.18.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](https://github.com/urllib3/urllib3/compare/1.26.17...1.26.18)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-type: direct:production
...

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examples/research_projects/decision_transformer/requirements.txt

@@ -229,7 +229,7 @@ tzlocal==4.1
 unidic==1.1.0
 unidic-lite==1.0.8
 uritemplate==4.1.1
-urllib3==1.26.17
+urllib3==1.26.18
 wasabi==0.9.0
 wcwidth==0.2.5
 websocket-client==1.3.1