Use new way to upload files

See https://github.com/actions/upload-artifact/blob/main/docs/MIGRATION.md#multiple-uploads-to-the-same-named-artifact

Signed-off-by: Philippe Ombredanne <pombredanne@nexb.com>

.github/workflows/test-and-build.yml

@@ -83,6 +83,7 @@ jobs:
             - name: Collect built wheels
               uses: actions/upload-artifact@v4
               with:
+                  name: intbitset-wheels-${{ matrix.os }}-${{ matrix.ach }}-${{ matrix.type }}
                   path: wheelhouse/*.whl
 
     build_sdist:
@@ -104,8 +105,21 @@ jobs:
           - name: Collect built sdist
             uses: actions/upload-artifact@v4
             with:
+                name: intbitset-sdist
                 path: dist/*.tar.gz
 
+    merge:
+      runs-on: ubuntu-latest
+      needs:
+        - build_sdist
+        - build_wheels
+      steps:
+        - name: Merge created wheels and sdist in a single zip
+          uses: actions/upload-artifact/merge@v4
+          with:
+            name: intbitset-build
+            pattern: intbitset-*
+
     test_on_many_oses:
         name: Run tests ${{ matrix.python }} on ${{ matrix.os }}
         runs-on: ${{ matrix.os }}