Bump actions/upload-artifact from 5 to 6

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

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

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

Author: dependabot[bot]

.github/workflows/build.yaml

@@ -100,7 +100,7 @@ jobs:
           python -m tox run -m ci -- --junitxml pytest.{envname}.xml
           python -m tox run -e cov_combine,cov_report
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         with:
           name: pytest-report-py${{ matrix.py }}-${{ matrix.os }}
           path: pytest.*.xml

.github/workflows/publish_to_pypi.yaml

@@ -22,7 +22,7 @@ jobs:
       - name: Check Dists (twine)
         run: twine check dist/*
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         with:
           name: packages
           path: dist/*

.github/workflows/publish_to_test_pypi.yaml

@@ -37,7 +37,7 @@ jobs:
       - name: Check Dists (twine)
         run: twine check dist/*
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         with:
           name: packages
           path: dist/*