Bump dash from 2.14.0 to 2.15.0

Bumps [dash](https://github.com/plotly/dash) from 2.14.0 to 2.15.0.
- [Release notes](https://github.com/plotly/dash/releases)
- [Changelog](https://github.com/plotly/dash/blob/dev/CHANGELOG.md)
- [Commits](plotly/dash@v2.14.0...v2.15.0)

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

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