Bump actions/upload-artifact from 4 to 6

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 4 to 6.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v4...v6)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/CI.yml

@@ -49,7 +49,7 @@ jobs:
           sccache: ${{ !startsWith(github.ref, 'refs/tags/') }}
           manylinux: auto
       - name: Upload wheels
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: wheels-linux-${{ matrix.platform.target }}
           path: dist
@@ -105,7 +105,7 @@ jobs:
           sccache: ${{ !startsWith(github.ref, 'refs/tags/') }}
           manylinux: musllinux_1_2
       - name: Upload wheels
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: wheels-musllinux-${{ matrix.platform.target }}
           path: dist
@@ -162,7 +162,7 @@ jobs:
           args: --release --out dist --find-interpreter
           sccache: ${{ !startsWith(github.ref, 'refs/tags/') }}
       - name: Upload wheels
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: wheels-windows-${{ matrix.platform.target }}
           path: dist
@@ -198,7 +198,7 @@ jobs:
           args: --release --out dist --find-interpreter
           sccache: ${{ !startsWith(github.ref, 'refs/tags/') }}
       - name: Upload wheels
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: wheels-macos-${{ matrix.platform.target }}
           path: dist
@@ -221,7 +221,7 @@ jobs:
           command: sdist
           args: --out dist
       - name: Upload sdist
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: wheels-sdist
           path: dist