Bump actions/download-artifact from 4 to 8

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 8.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...v8)

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

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/pypi.yml

@@ -103,7 +103,7 @@ jobs:
     permissions:
       id-token: write
     steps:
-      - uses: actions/download-artifact@v7
+      - uses: actions/download-artifact@v8
         with:
           pattern: wheels-*
           merge-multiple: true

.github/workflows/release.yml

@@ -135,7 +135,7 @@ jobs:
         run: ${{ matrix.install_dist.run }}
       # Get the dist-manifest
       - name: Fetch local artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           pattern: artifacts-*
           path: target/distrib/
@@ -184,14 +184,14 @@ jobs:
           persist-credentials: false
           submodules: recursive
       - name: Install cached dist
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: cargo-dist-cache
           path: ~/.cargo/bin/
       - run: chmod +x ~/.cargo/bin/dist
       # Get all the local artifacts for the global tasks to use (for e.g. checksums)
       - name: Fetch local artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           pattern: artifacts-*
           path: target/distrib/
@@ -234,14 +234,14 @@ jobs:
           persist-credentials: false
           submodules: recursive
       - name: Install cached dist
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: cargo-dist-cache
           path: ~/.cargo/bin/
       - run: chmod +x ~/.cargo/bin/dist
       # Fetch artifacts from scratch-storage
       - name: Fetch artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           pattern: artifacts-*
           path: target/distrib/
@@ -261,7 +261,7 @@ jobs:
           path: dist-manifest.json
       # Create a GitHub Release while uploading all files to it
       - name: "Download GitHub Artifacts"
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           pattern: artifacts-*
           path: artifacts