GitLab

Bump dash in /examples/research_projects/decision_transformer

Bumps [dash](https://github.com/plotly/dash) from 2.3.0 to 2.15.0.
- [Release notes](https://github.com/plotly/dash/releases)
- [Changelog](https://github.com/plotly/dash/blob/dev/CHANGELOG.md)
- [Commits](https://github.com/plotly/dash/compare/v2.3.0...v2.15.0

)

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