Update GitHub Actions to use latest artifact upload and download versions

Author: PierreRaybaut

.github/workflows/build_deploy.yml

@@ -26,7 +26,7 @@ jobs:
         env:
           CIBW_BEFORE_BUILD: pip install babel && pybabel compile -d plotpy/locale -D plotpy
 
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v6
         with:
           name: cibw-wheels-${{ matrix.os }}-${{ strategy.job-index }}
           path: ./wheelhouse/*.whl
@@ -48,7 +48,7 @@ jobs:
       - name: Build sdist
         run: pipx run build --sdist
 
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v6
         with:
           name: cibw-sdist
           path: dist/*.tar.gz
@@ -61,7 +61,7 @@ jobs:
       id-token: write
     if: github.event_name == 'release' && github.event.action == 'published'
     steps:
-      - uses: actions/download-artifact@v4
+      - uses: actions/download-artifact@v7
         with:
           # unpacks all CIBW artifacts into dist/
           pattern: cibw-*