Bump actions/setup-python from 5 to 6

Bumps [actions/setup-python](https://github.com/actions/setup-python) from 5 to 6.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](actions/setup-python@v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/build.yaml

@@ -71,7 +71,7 @@ jobs:
           sudo apt-mark hold firefox grub-efi-${{ matrix.arch == 'arm64' && 'arm64' || 'amd64' }}-signed
           sudo apt update && sudo apt upgrade
           sudo apt install lcov llvm
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with:
           python-version: '>=3.9'
       - name: Install Ubuntu's Qt5