build(deps): update pyside6 requirement from ~=6.8.2 to ~=6.9.0

Updates the requirements on [pyside6](https://pyside.org) to permit the latest version.

---
updated-dependencies:
- dependency-name: pyside6
  dependency-version: 6.9.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements.txt

@@ -1,7 +1,7 @@
 PyYAML~=6.0.2
 psutil~=7.0.0
 pynvml~=12.0.0
-PySide6~=6.8.2
+PySide6~=6.9.0
 safetensors~=0.5.2
 numpy<2.0.0
 torch~=2.5.1