Bump pyside6 from 6.9.1 to 6.9.3

Bumps [pyside6](https://pyside.org) from 6.9.1 to 6.9.3.

---
updated-dependencies:
- dependency-name: pyside6
  dependency-version: 6.9.3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

pyproject.toml

@@ -38,4 +38,4 @@ content-type = "text/markdown"
 find = { namespaces = false }
 
 [project.optional-dependencies]
-gui = ["PySide6==6.9.1", "qt-material"]
+gui = ["PySide6==6.9.3", "qt-material"]