Bump plotly from 5.18.0 to 5.19.0 in /code

Bumps [plotly](https://github.com/plotly/plotly.py) from 5.18.0 to 5.19.0.
- [Release notes](https://github.com/plotly/plotly.py/releases)
- [Changelog](https://github.com/plotly/plotly.py/blob/master/CHANGELOG.md)
- [Commits](plotly/plotly.py@v5.18.0...v5.19.0)

---
updated-dependencies:
- dependency-name: plotly
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

code/requirements.txt

@@ -2,7 +2,7 @@ azure-functions==1.18.0
 streamlit==1.30.0
 openai==0.27.8
 matplotlib==3.8.2
-plotly==5.18.0
+plotly==5.19.0
 scipy==1.12.0
 scikit-learn==1.4.0
 transformers==4.37.2