Bump actions/upload-artifact from 6 to 7 in /.github/workflows

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/ci.yml

@@ -58,7 +58,7 @@ jobs:
           fi
 
       - name: Upload coverage data
-        uses: actions/upload-artifact@v6
+        uses: actions/upload-artifact@v7
         with:
           name: coverage-data-${{ matrix.python-version }}
           path: .coverage.*
@@ -100,7 +100,7 @@ jobs:
           echo '```' >> $GITHUB_STEP_SUMMARY
 
       - name: Upload HTML report
-        uses: actions/upload-artifact@v6
+        uses: actions/upload-artifact@v7
         with:
           name: html-report
           path: reports/coverage/html

.github/workflows/release.yml

@@ -50,7 +50,7 @@ jobs:
           fresh_env/bin/python -c "import xarray_validate; print(xarray_validate.__version__)"
 
       - name: Store distribution packages
-        uses: actions/upload-artifact@v6
+        uses: actions/upload-artifact@v7
         with:
           name: python-package-distributions
           path: dist/