Bump actions/upload-artifact from 6 to 7

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 6 to 7.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v6...v7)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/docs.yml

@@ -102,7 +102,7 @@ jobs:
       # Store the docs as a build artifact so we can deploy it later
       - name: Upload HTML documentation as an artifact
         if: success()
-        uses: actions/upload-artifact@v6
+        uses: actions/upload-artifact@v7
         with:
           name: docs-${{ github.sha }}
           path: doc/_build/html

.github/workflows/pypi.yml

@@ -81,7 +81,7 @@ jobs:
       - name: Upload archives as artifacts
         # Only if not a pull request
         if: success() && github.event_name != 'pull_request'
-        uses: actions/upload-artifact@v6
+        uses: actions/upload-artifact@v7
         with:
           name: pypi-${{ github.sha }}
           path: dist

.github/workflows/test.yml

@@ -150,7 +150,7 @@ jobs:
         run: coverage xml
 
       - name: Upload coverage report as an artifact
-        uses: actions/upload-artifact@v6
+        uses: actions/upload-artifact@v7
         with:
           name: coverage_${{ matrix.os }}_${{ matrix.dependencies }}
           path: ./coverage.xml