Bump the github-actions group with 2 updates

Bumps the github-actions group with 2 updates: [actions/upload-artifact](https://github.com/actions/upload-artifact) and [actions/download-artifact](https://github.com/actions/download-artifact).


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

Updates `actions/download-artifact` from 7 to 8
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v7...v8)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions
- dependency-name: actions/download-artifact
  dependency-version: '8'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions
...

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

Author: dependabot[bot]

.github/workflows/publish.yml

@@ -1,4 +1,4 @@
-# Publish new release on PyPI.
+# Publish new release on PyPI.
 name: Publish release
 
 on: [workflow_dispatch]
@@ -24,7 +24,7 @@ jobs:
           run:  flit build --format wheel
 
         - name: Store wheel.
-          uses: actions/upload-artifact@v6
+          uses: actions/upload-artifact@v7
           with:
             name: wheel
             path: dist
@@ -42,7 +42,7 @@ jobs:
       steps:
 
         - name: Download wheel.
-          uses: actions/download-artifact@v7
+          uses: actions/download-artifact@v8
           with:
             name: wheel
             path: dist