Update GH CI to use upload/download-artifact@v4

This required some structural changes, because v4 no longer allows
multiple matrix jobs to upload to the same artifact and have the results
merged. So instead every job creates its own artifact and there is a
final merge process (which also handles combining the debug symbols into
a tarball).

.github/workflows/test.yml

@@ -227,7 +227,7 @@ jobs:
         run: ./.ci/py-requirements.sh
       - run: pip install build==0.10.0
       - run: python -m build --sdist .
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: sdist
           path: ./dist/*.tar.gz
@@ -254,13 +254,13 @@ jobs:
         env:
           CIBW_ARCHS: ${{ matrix.arch }}
           CIBW_BUILD: ${{ matrix.python }}-manylinux*
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
-          name: wheels
+          name: wheel_linux-${{ matrix.arch }}-${{ matrix.python }}
           path: ./wheelhouse/*.whl
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
-          name: debug_symbols_uncompressed
+          name: debug_symbols_uncompressed-${{ matrix.arch }}-${{ matrix.python }}
           path: ./wheelhouse/*.debug
 
   cibuildwheel-macos:
@@ -282,23 +282,40 @@ jobs:
           CIBW_ARCHS: ${{ matrix.arch }}
           CIBW_BUILD: ${{ matrix.python }}-macos*
           CIBW_TEST_SKIP: "*-macosx_arm64"
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
-          name: wheels
+          name: wheel_macos-${{ matrix.arch }}-${{ matrix.python }}
           path: ./wheelhouse/*.whl
 
-  compress-debug:
-    needs: [cibuildwheel-linux]
+  combine:
+    needs: [cibuildwheel-linux, cibuildwheel-macos, sdist]
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/download-artifact@v3
+      - name: Create paths
+        run: mkdir -p debug-symbols dist wheelhouse
+      - uses: actions/download-artifact@v4
         with:
-          name: debug_symbols_uncompressed
+          pattern: debug_symbols_uncompressed-*
+          path: .
+          merge-multiple: true
+      - uses: actions/download-artifact@v4
+        with:
+          pattern: wheel_*
+          path: wheelhouse/
+          merge-multiple: true
+      - uses: actions/download-artifact@v4
+        with:
+          name: sdist
+          path: dist/
+          merge-multiple: true
       - name: Compress debug symbols
         run: >-
-          tar -Jcvf "spead2-"$(<VERSION.txt)-debug.tar.xz _spead2*.debug
-      - uses: actions/upload-artifact@v3
+          tar -Jcvf debug-symbols/"spead2-"$(<VERSION.txt)-debug.tar.xz _spead2*.debug
+      - uses: actions/upload-artifact@v4
         with:
-          name: debug_symbols
-          path: spead2-*-debug.tar.xz
+          name: combined
+          path: |
+            debug-symbols/
+            dist/
+            wheelhouse/