Update voila requirement from ~=0.3.6 to ~=0.4.0

Updates the requirements on [voila](https://github.com/voila-dashboards/voila) to permit the latest version.
- [Release notes](https://github.com/voila-dashboards/voila/releases)
- [Changelog](https://github.com/voila-dashboards/voila/blob/main/CHANGELOG.md)
- [Commits](https://github.com/voila-dashboards/voila/compare/@voila-dashboards/voila@0.3.6...@voila-dashboards/voila@0.4.0)

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

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

requirements.txt

@@ -1,5 +1,5 @@
 pip~=22.3
-voila~=0.3.6
+voila~=0.4.0
 matplotlib~=3.6.2
 numpy~=1.23.4
 ipympl~=0.8.8