Update GitHub Artifact Actions

Author: renovate[bot]

.github/workflows/repos.yaml

@@ -40,7 +40,7 @@ jobs:
       - name: Package distribution
         run: tar -C scip-java/build/install -czf scip-java-dist.tgz scip-java
 
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v7
         with:
           name: scip-java-dist
           path: scip-java-dist.tgz
@@ -147,7 +147,7 @@ jobs:
 
       - uses: DeterminateSystems/magic-nix-cache-action@v14
 
-      - uses: actions/download-artifact@v4
+      - uses: actions/download-artifact@v8
         with:
           name: scip-java-dist
           path: scip-java-dist